It was Two-Pie Tuesday: Cowboy star Roy Rogers and New York Mayor Abe Beame, 240 miles apart, both got hit with pies. But nobody was laughing.

It used to be a sure thing - Chaplin did it, and the Mack Sennett cops, Laurel and Hardy. Soupy Sales made a career of it on TV. He estimated he was hit 19,000 times by pies. Milton Berle, Red Skelton . . . remember the fight in the pie shop in "The Great Race"?

Nine guys throwing hundreds of pies in all directions, so splattered they look like vertical banana splits, and Tony Curtis strolls through, immaculate in a blinding white suit. He's thinking of something else. Straight through the middle of this blizzard of pies he walks, untouched, unflecked, gleaming. It goes on for minutes, unbearably. He walks and walks, so clean, so white. And then . . . .

Tt used to be a sure thing. There was something funny about a pie. You couldn't do it with a bowl of mine-strone. It was violent, but innocent. Just like America, some would say. "Just kiddin', Mister." Good clean fun.

In theory not only is anger vented but the victim is made to look foolish. "For a couple of moments," Sales told one reporter, "it turns the big guys into slobs, puts them on the same level as everyone else."

The fad peaked in 1975. By then we Americans, as is our custom, had turned it into a business, with firms in a half-dozen cities who would throw a pie for about $35 at anyone you specified: Pie Face International, Pie Kill Ltd., Pies Unlimited, Pie in the Eye.

Well, American humor always has been a bit rough. But one detects a new note.

"It's the closet I'll ever get to ordering a Mafia rub-out," one client was quoted. Somewhere along the line, the humor was being left behind. The laugh was hardening.

Today, the business languishes. Companies listed in phone books from Washington to San Francisco seem to be gone. Pie Face San Francisco is now a law office.

These days when a public figure sees a face pushing suddenly out of the crowd, the first thought is it's probably an assassin.

Pie-throwing has become political. The pie isn't thrown, it is shoved into the face. And the thrower, it turns out afterward, didn't think it was funny either. He's only interested in making some pitch or other.

Beame, who almost dodged an apple pie at a campaign debate, declined to press charges against a man identified as Aaron Kaye, the man who scored a Banana cream pie in the face of Daniel Patrick Moynihan in last fall's senatorial campaign. The youth who hit Rogers at a promotion in Fairfax was charged with disorderly conduct.

Kaye, a Yippie and a writer for The Yipster Times, has thrown political pies before, one recalls. It is all very serious and purposeful and humorless.

"A man being hit with a pie, isn't funny," Sales once said, "unless a foundation has been built that leads up to the pie. It has to come as a resonable climax."

The throwing is important esthetically, too. There is something about that round soft thing flying through the air to splat with prescient accuracy on a face. Merely smearing it on somebody is just kind of nasty.

Certainly it doesn't amuse the targets.

Moynihan called the attack on him "a violent act" and said, "It scared hell out of me." He thought it was acid at first. But he didn't press charges. High school students in Fairfax County were suspended for their pie pranks in 1975, and this spring a Loudoun County senior almost didn't graduate after she pied the face of the vice principal.

Maybe a few years ago the pie victim felt honorbound to grin and shrug it off, but no more. We have learned not to let ourselves be assaulted in the spirit of good clean fun.