It was Meryl Streep’s idea to auction off The Devil Wears Prada’s couture costumes to benefit women’s charities at the St. Regis last week, but it was surprise lots from the stars that brought in the big bucks. Christine Schwarzman (wife of Steve) paid $8,000 for drinks and shoe shopping with Stanley Tucci. Then Anne Hathaway offered her baby-sitting services. “You have to prove you actually have children, according to my boyfriend,” she joked. “Come on! Give your kids a memory! I’ll bring cupcakes!” Bidding was so furious that, at CAA honcho Kevin Huvane’s request, Hathaway sold two two-hour gigs at $20,000 apiece (the buyers were Dan and Cynthia Lufkin and Craig and Caryn Effron, whose East Seventies townhouse was Streep’s home in the movie). Streep offered to dish Hollywood dirt at tea (“mar-tea-ni”) at the St. Regis, but by then the room’s fervor had died down. “Anne Hathaway, you paid more for her. Don’t think I didn’t notice,” Streep said with a sigh, before raising her hand and volunteering “$17,000 . . . to drink alone.” A minute later, a Public Theater board member bought the tea for $18,000.