IT WILL astonish restaurant employes and patrons alike to hear this, but even the best resturants are commercial estblishments where people pay to be served meals, and are not temples of social behavior where they submit themselves to be judged.

It astonishes Miss Manners to hear that many people who are confident of their behavior among their friends become terrified of embarrassing themselves before the imposing figures of maitre d's, as they call themselves, or other high officers in the restaurant service. One would think that if the people sitting at one's restaurant table are satisfied with one's manners, one would hardly care about the opinion of those standing behind it.

This odd state of affairs, a reversal of the usual customer-serviceperson relationship -- paralleled only among patients and the doctors they hire -- seems to have come about by the design of restaurant managers. Many of them believe that their patrons are sycophants who only respect those who look down upon them, and their success has proven them often correct.

The fact is that few restaurants, no matter how outrageously expensive, can provide formal service as it is known in social circumstances. It is rare, indeed, to dine in a restaurant where the service people do not interrupt the diners, where filled plates are never put before one and where trays, rather than hands, are used to bring needed equipment. To those who believe that a fancy restaurant represents dining of a class higher than that to which they are accustomed, Miss Manners must explain that there is no need to feel inadequate. Good restaurant service may be pleasant and smooth, but it does not represent the equivalent of butlers and footmen.

As you are paying for your meal in a restaurant, it is perfectly proper to:

* Request a table in an area you prefer, say, near a window or away from musicians. For a customer to accept the employes' or owners' ideas of "good" tables and "bad" tables and compete to be favored with their choices is childish.

* Sit next to whomever you want among those in your group. Unless one is giving a party in a restaurant, the social rules about seating do not apply. If couples want to sit next to, rather than across from, each other, or with the gentleman, rather than the lady, against the wall, Miss Manners cannot see why they should not be permitted to do so.

* Know what is being offered, in the way of food and drink, and its price. If a list of "specials of the day" is recited, it is sensible to ask how much a dish will cost.

* Expect to be supplied with correct flatware, and resupplied, discreetly and tactfully, with replacements for dropped or misused implements.

* Talk only with those with whom one is dining. If strolling musicians, itinerant fashion models or sociable waiters or other servicepeople present themselves, they may be dismissed with a pleasant but abstracted nod.

* Remain ignorant of the personnel hierarchy of the restaurant. If a restaurant employs an army of captains, waiters, headwaiters, priests of wine, busboys and hostesses, that is its privilege. But the customer should not be expected to recognize and treat according to rank the entire service. He may address any request to whomever presents himself with the expectation that that person, if not designated to perform the task, will find the person who is. Unless some special favor is given, the client should only have to leave one tip, to be divided by those involved according to their own standards.

* Enjoy his dinner, free of worries about the help critiquing his manners. Only Miss Manners is allowed to do that.MISS MANNERS RESPONDS

Q. What is the best way for a girl to ask a boy for a date?

A. What is the best way for a boy to ask a girl for a date? In such a way that it can be refused without insult.

Note that Miss Manners did not say without heartbreak, or without discouragement. These may be inevitable, but they may be suffered in private, without the humiliation of their being shared. If you consider the difference between a negative response to "Are you free on next Tuesday to go roller-skating?" and one to "Would you like to go out some time?" you will understand what Miss Manners means.

Q. It seems that all my friends are having babies these days. How soon after the birth is it polite to ask them out? Should we allow them to bring the baby with them?

We don't have children, and are not sure we ever will, but we don't want to drift away from our friends who do. What adjustments should we make for them in our social lives?

A. The chief kindness is to remember that your friends now have children, and to try not to hold it against them. That is, you must appear to sympathize with both their admiration for their babies, and their difficulties in parking the children with responsible people so that they can get away from them.

Of course, you have paid a visit to each newborn and expressed your appreciation of its beauty. And of course, you will continue to include your friends in your usual social activities, giving them time to make arrangements for baby-sitters.

Allow Miss Manners to suggest some other social niceties:

Soon after the baby is born, before the mother is prepared to go out, you might invite the new parents to a dinner in their own home. You cook, you serve -- on trays, if necessary -- and you clean up. This can be counted as a baby present.

If you have several friends with new babies, you might give a party at which you provide a baby-sitter. Each couple brings its baby, but turns it iver to your sitter, in a part of your house as remote from the festivities as possible.

Schedule interruptable social events, at which your friends may bring their babies. A relaxed Sunday teatime, for example, isn't marred if a parent has to get up at feeding or crying time, but a seated dinner is.

Q. The question which has currently ripped me apart from my fiance''s family is: Is it correct to invite persons to a wedding some six hours away from their homes and then not serve them hard liquor?

I have been accused of being insensitive to our guests' comfort, since, in the interest of saving money, I have opted to serve only wine and omit hard liquor. (I might add that I am planning the wedding on my own, since my family lives across the country, and we are having a sit-down lunch, music, a beautiful reception in a well-known hotel, etc.) Since I cannot contribute much financially, I really don't want to go hog-wild with my fiance''s money and then be accused of who-knows-what. I honestly don't see how anyone could go away from our wedding "disappointed," as I've been told will happen if we don't serve hard liquor.

I've also been told by a certain member of his family (not his mother) that I must consider how much certain relatives and friends are "putting out" in terms of their gift to us, hotel bill, gas, etc. Am I wrong not to consider how much they spend relative to how much we spend? I feel I am doing everything in my power to assure that everyone will be comfortable and happy.

My fiance' can afford to serve hard liquor, but I can't, and I'm not comfortable with him footing the entire bill. I simply want to know if my present arrangements are tacky or inconsiderate of others.

A. Have you considered scaling the drink service to the price of the present? The person who gives you a toaster would get one drink of ordinary Scotch, the donor of the kitchen machine would get three drinks of an expensive blend, and the one who came across with the silver tea set would be entitled to get blotto and pass out on the wedding cake.

Surely this would be in keeping with the tenor of the arguments being employed by your new family.

Your points are slightly better, but not much. You could argue the money angle if you were paying the entire bill and could not afford liquor, but the charm of wanting to spare your fiance' the expense is lessened by the fact that he wants to spend the money, and that not doing so is making trouble for him with his family.

Allow Miss Manners to propose some entirely different points, not only to keep this argument going (prenuptial cross-family fights are a tradition and if it weren't over this, it would be over something else), but to get it on a higher plane.

1. No one is "entitled" to liquor at a social event. Whatever reasons the hosts have for not serving it -- religious, social, financial -- are none of the guests' business. Their duty is to drink or not drink what is offered, and to refrain from complaints. (If it is any comfort, Miss Manners will confide that she has seen distinguished American and European officials behave like spoiled children when discovering, at some of the parties in Arab embassies, that no liquor was to be served. Their anguish is particularly offensive when one is aware that these people are likely to attend two or three wet diplomatic receptions on the same evening.)

2. Champagne is the proper drink at a wedding reception. Champagne is a wine, but people tend not to complain about its being substituted for cocktails because they know it's expensive. Champagne comes in many prices.

3. If liquor is absolutely necessary to the comfort of anyone, that person should not be drinking.

4. People who have six-hour rides ahead of them should not be drinking.

5. No matter how much liquor is served at a wedding reception, there will be some relatives who will go away feeling disappointed. Those related to the bride will be thinking that she could have done better, and those related to the bridegroom will think he could have.

Feeling incorrect? Address your etiquette questions (in black or blue-black ink on white writing paper) to Miss Manners, in care of this newspaper. 1981, United Feature Syndicate Inc.