There are only 2 drive-through sports books in Las Vegas--at the Imperial Palace and at the Fiesta.
At the Imperial Palace, bets are made in person, with a live book attendant stationed at the drive-through window. The latest lines are posted outside, and a second lane is opened for busy days during the football season.
At the Fiesta, drive-through bets are made bank-style, with money and betting slips going between customers and book attendants through tubes along each of the three lanes. Overhead television screens give patrons the latest lines, and two-way speakers allow for conversations between patrons and attendants.
One thing Fiesta and Imperial Palace drive-up customers can't do outside is cash a winning ticket--that's something they are required to do in person inside. Customers also can't bet on horse racing from their cars, with both casinos only offering that option in the book itself.