Cowboy rides up to a saloon. The bartender, the only person in the saloon, watches through the window as the cowboy gets down off his horse, walks around behind the horse, raises the horse's tail, kisses the horse's butt, then walks into the saloon and orders a drink.
Bartender gets the drink and tells the cowboy it's free if he'll just tell him why he kissed the horse's butt.
Cowboy says, "Well, bartender, see...I got these TERRIBLE chapped lips."
Bartender says, "Now you ain't gonna tell me kissin' a horse's butt cures chapped lips, are ya'?"
Cowboy says, "Naw, but it sho' do keep y'from LICKIN' 'em!"