FOR MANY PEOPLE, summer is the most pleasant time of year. It's the season for beaches and picnics, sunshine and sandals. For a restaurant critic, though, it is cockroach season. The complaints about cockroaches in restaurants multiply with the heat. And I spend extra time explaining to disgusted diners that just about all restaurants, particularly urban restaurants and those adjacent to construction or renovation, get a cockroach once in awhile. It doesn't necessarily mean the restaurant is dirty.

Of course some restaurateurs are too blase about cockroaches, and some don't have either the decency or good sense to apologize and try to reinstate the diners' comfort. On the other hand, some diners seem to want outlandish compensation for having spotted a cockroach in the restaurant.

One diner wrote me to report four cockroaches in a downtown restaurant (which happens to share the block with a construction site). Her party moved to a table away from the wall and continued their meal. Afterwards, the waitress told them that dessert was on the house as an apology for the bugs, and another staff member came to explain to them that the restaurant had recently been sprayed. The diner was unsatisfied; a free dessert and an apology were insufficient, she wrote. She wanted to know, what did I think?

I think the restaurant behaved appropriately. It treated the complaint seriously, apologized and explained, then offered the free dessert as a friendly gesture.

While the customer thought that was not enough, I wonder what more would have been warranted. A free meal? Why? Clearly the diners didn't consider the meal contaminated, but ate it and stayed through dessert. If they thought cockroaches a danger, why did they eat the meal? And why should they not pay for a meal they ate?

Some diners consider any flaw in a restaurant justification for a free meal, just as some consider any flaw in the service justification for not paying a tip. But a free meal is not free to the restaurant. And in our system a tip is not a bonus, but the basic wages of the waiter. I'm sure restaurants would love to charge diners for spilling their wine on the carpet or for breaking a glass. They'd be happy for a diner to offer them compensation for making the waiter's or the kitchen's job more difficult in some way. But I have never heard of a diner making such an offer, while I often hear from diners who expect it from a restaurant.

This doesn't mean a restaurant should shrug off a cockroach -- as many a restaurant does. But what diners should expect is concern and apologies, not a $50 bounty for cockroach-spotting.

Phyllis C. Richman's restaurant reviews appear Sundays in The Washington Post Magazine.