Humpty's "Surprise"

Puss hears Humpty being hassled by Jack and Jill, even trying to bribe them with eggs from the Golden Goose. When Puss catches up with them, however, Humpty was merely getting a champagne bottle ready before revealing it's a surprise party and that Jack and Jill, as well as the cager and his white cat from the beginning of the movie as well as the 3 bar patrons all work for him.

Example of:
Bait-and-Switch