A bouncer at Spirit, a club on West 27th Street in Manhattan, checking young women's IDs. Many say underage patrons have no trouble getting in. The velvet rope outside one of Manhattan's trendiest nightclubs was but a gateway for Michael, a 19-year-old from Long Island. Followed by his four male friends, all 19 or 20, he sashayed past a stagnant line of 50 people waiting outside Mood NY during the early morning hours Saturday. From a pocket inside his black sports jacket, he pulled out his Bank of America credit card and whispered to the bouncer that he planned...