NEW YORK (AdAge.com) -- In 2008, as gasoline prices topped $4, sales of 75 mpg Vespa scooters spiked to record levels. But in the first two quarters of this year, sales have dropped just as dramatically for the Piaggio subsidiary. But Vespa marketing campaigns continue at full throttle. Last week, the parking lot of Central Park's Tavern on The Green was turned into a maze of test riding tracks for members of the media. And Piaggio Americas' CEO predicted that U.S. consumers would become serious scooter users over the next five years.