I had a dog that did that. They do it because you don't smell like yourself after a shower (soap, shampoo, lotion...) and they want you to smell "normal."
My poor dog barked at me when I got out of the shower and dried off. He sniffed my legs in that "Whoa! What's this new smell?" pose, and decided I wasn't Mom.
Wednesday couldn’t care less, of course, but Shannon is very into washing people and things that don’t smell the way she thinks they should.
I had a dog that did that.
I have a Dachshund/Chihuahua mutt that does that. He'll wait outside the bathroom when he hears the shower. Crazy mutt.