THOUGH THOUSANDS of laid-off federal employees will remember Ronald Reagan best as the president who showed them the door in 1981, many more government workers will remember him as the protector of their cherished lots--where they will park their cars at taxpayers' expense with the full blessing and commitment of Mr. Reagan.

Their first break in this battle against paying parking fees came last March, when U.S. District Judge Harold H. Greene ruled that a fee program ordered by President Carter was illegal because it had not been approved by Congress. But that was upset in December, when a 3-to-0 appellate court decision said the president did have the legal authority, under a law that provides for economical use of government property.

But the next day, President Reagan said he was foursquare behind free parking--which, everyone should realize, will cost America's taxpayers an estimated $40 million a year to subsidize. And so much for anyone who isn't on the receiving end of this government giveaway.

The parking-fee policy wasn't meant as a punishment or slap at federal workers, but as a signal in federal energy and transportation policy. It should be coupled with sympathy and help for those workers who may have few alternatives because bus and rail service is still poor in their neighborhoods or during their commuter hours. But direct government subsidies for driving to work have no place in tight-money, tight-energy times.