PEOPLE WHO WEREN'T around here in the days before the District of Columbia won a measure of home rule from its federal overseers are often amused by tales of all the restrictions that once governed local behavior. But many residents who remember those times less than fondly get understandably jumpy when a congressman starts threatening the local franchise. And if there's one member of Congress who ought to know this, it's the representative from just across the river, Frank Wolf.

Yet during a House Appropriations subcommittee hearing on the city's fiscal 1987 budget Mr. Wolf issued a threat worthy of those bad old days: he threatened to seek cuts in the federal payment to the District if Mayor Barry and D.C. Council Chairman David A. Clarke do not work to raise the legal drinking age in the District from 18 to 21.

Quite aside from how these two elected local leaders and their constituents may feel about the drinking age, the implications of Mr. Wolf's threat go beyond anybody's eligibility for a six-pack. Who else on the Hill has a pet project for the mayor and council chairman to get after? Will some hard-drinking colleague threaten to rip apart the city's budget if the mayor doesn't keep the taverns open all night? What if some senator says he wants all the taxis in town painted purple before he'll support a penny more for the Public Service Commission?

There's nothing wrong with a little consultation between Mr. Wolf and leaders of the local government about any matter of interest to the city's neighbors. But how would he like it if the mayor and council of the District had the power to savage the budget of Arlington unless the county board agreed to offer 18 percent of its government jobs to D.C. residents?

Stretches of the imagination? Or shades of the days when Congress decided everything from the maximum length of dog leashes to the layout of cab zones? Home rule may be relatively young here -- going on 11 1/2 -- but last time we checked, that was a legal age for local decision-making.