From Muppet Wiki

Fozzie can't seem to catch a break. He's playing with his sticker collection at home when Kermit comes over to invite him to help paint the clubhouse. Fozzie immediately puts on an old shirt and pants, and rushes out to help. Instead of admiring Fozzie's solid work ethic and concern for his clothes, his mother sighs because he left his stickers on the floor.

Unattended, Fozzie's baby brother Freddie finds the stickers, and sticks them on every surface in the living room. Fozzie's father and mother must not have noticed Freddie going to town with the stickers, even though when we last saw them, they were sitting in the same room.

When Fozzie comes home, he gets a stern lecture about how irresponsible he is.