THE SO-CALLED ALL Savers certificate seems, in its first two days on sale, to be a huge success. Customers stood anxiously in long lines to buy them, and at least one savings and loan association kept its offices open until midnight Friday to handle the flow. But it's useful to recall the price at which this triumph is being purchased, and at whose expense.

Congress created the All Savers certificates to bail out the savings and loan industry, much as it earlier bailed out the Chrysler Corporation. The difference is that in the Chrysler case, Congress used only guaranteed loans. With the All Savers certificate, the government is paying actual tax subsidies to upper-bracket taxpayers--it benefits only people in a 30 percent bracket or higher--on the condition that they pass some of that subsidy on to an S&L association or a bank. What's the cost in tax losses? It's not yet possible to know. But it will certainly be larger than the congressional estimate of $3.3 billion over three years.

The losers in this deal, along with the Treasury, are the municipal borrowers. For the first time they have a tax-exempt competitor--and it's offering a much higher interest rate than the municipals have been paying. Congress evidently never thought of the effect on the muncipal market when it created the All Savers certificate.

As for the housing industry and the mortgage interest rates, the new certificate seems likely to have little or no effect. Congress tried to write the law to require the S&Ls to share some of this bounty with the home builders. But it won't work. The certificate is a one-year investment, and not much of that money will be reinvested in 20-year mortgages.

The certificate will indeed help the S&Ls, with an infusion of money at interest rates lower than they can find anywhere else. But the method is grotesquely inefficient, for a very large share--probably half--of the certificates will be sold by banks, which hardly need the help. It is a classically bad policy, spraying enormous subsidies around wildly in the hope that some minor fraction of them will come to rest in distressed businesses. It would have been much cheaper if Congress had simply provided interest-free loans to S&Ls in trouble.