Donald Shoup believes many drivers share the curbside parking philosophy of "Seinfeld"'s George Costanza: "It's like going to a prostitute. Why should I pay when, if I apply myself, maybe I could get it for free?"But Shoup, an urban planning professor at the University of California, Los Angeles, thinks New York's parking should cost more if it wants to cut congestion."I think people who pay $200 for 'Spamalot' could park in front of the theater for $10 an hour," said Shoup yesterday at a press event held by Transportation Alternatives, a group that brought him here to meet with the Dept. of Transportation, NYPD and business leaders.A big culprit is "hunting for a spot," said Shoup, citing a study in SoHo where 28 percent of drivers surveyed were searching for curbside parking. A similar study in Park Slope found 45 percent of drivers cruising for spots.Shoup believes the city should set a price high enough to keep a couple of vacant spaces. Revenue could go to street cleaning and other improvements."It's like congestion pricing, but with huge difference: It can be done one block at a time and only for neighborhoods that want it," he explained.Barbara Adler of the Columbus Avenue Business Improvement District was interested. She hoped, in exchange, the DOT could provide "real benefits on our streets like a traffic-protected bike lane and other things for pedestrians."Street parking in London's tourist district costs $8 an hour, he said. Los Angeles recently introduced similar legislation."If there's any place for this, I think it would be Manhattan," said Shoup. "I would say 98 percent of the people would see a better environment and 2 percent would get a place to park if they're willing to pay."Plan in motionThe DOT?has removed thousands of single-space meters and replaced them with Muni-Meters, which allows for charging higher fares for longer stays.