Towards the end of the cartoon, when Elmer rings for Daffy, Daffy runs up to the front desk and says, "Yes, sir!" but his lips don't move. See more
And then... and then... here's the pay off. Oh, it'll kill ya! When the farmer says, "Do you expect to come back here next year?", the salesman said, the salesman says... The salesman answers, he says... Hey, what do you know, I forgot what the salesman did say. Oh, but it was a riot! The funniest thing I've ever heard!