"Thanks" the the Travel Channel and many messages here, towel animal art is close to a "demand", exceeding even an expectation. Towel animals are just what the name implies -- "animals" made from bath and/or face towels.
I don't think Mousekeeping provides classroom training on how to create towel animals. Also not all Mousekeepers have time to spend making these art creations in every room. It's not like this is the Mousekeeper's primary task -- they are, after all, paid to clean the room, make the beds, empty the trash, etc.
Some Mousekeepers know how to do this; others do not. Some may find time to do it; others may not have extra time.
Some Mousekeepers take stuffed animals left in the room and arrange them in windows or on beds; others don't. But again, this seems to have risen well past the level of a nice surprise past expectation almost to demand.
Despite these realities, some people are disappointed when they return from the parks and find no special surprises in the room. Maybe the Internet has cursed us by elevating what was once a nice surprise to something too often expected.
As I posted somewhere else, expectations can be hazardous to a vacation, especially at Disney.