The marketing masterminds behind Carl's Jr. know that sex sells: this year alone, the fast food franchise has featured lascivious spots starring seductresses such as Padma Lakshmi  and Audrina Partridge  suggestively scarfing down burgers. And CKE Restaurants , the parent company of Carl's Jr. and Hardee's, won't stop there. To kick off its new French Dip Thickburger, Hardee's has brought on four feisty "French Maids"  who will embark on a national tour, visiting stores and posing for photos. The ladies — appropriately named Sophie, Antoinette, Gabrielle, and Isabelle — hope to lure customers with short skirts, fishnet stockings, and plunging necklines. Consumers will be able to snap pictures with the maids and later locate the images online through a Hardee's microsite, French Me . With their risqué campaigns, the two eateries have certainly gotten media attention. But as they continue down a racy path, are the chains poised to become the fast food equivalent of Hooters? Is the company's marketing approach slick — or edging on vulgar?