LEXINGTON, Ky. − At the Keeneland September yearling sale, some consignments are almost as famous for their hospitality as they are for the horses they’ve sold. Free coffee, gourmet cookies, and doughnuts are there to tempt weary shoppers who spend hours on their feet sifting through the auction’s 4,319 yearlings. But some of those delectable spreads, which can keep buyers and their agents hanging around for a while where yearlings are showing, are more than friendly customer service for potential bidders.