Just a theory
Perhaps none of the users are particularly bad, it's just that there are a lot of them. Unfortunately it takes just one accident to wet the floor, and so the next person stands a bit further back to avoid making his hush puppies smell of wet dog, making it more likely he'll drip a bit on the floor... rinse and repeat. Except without much rinsing.

Also, see the broken windows theory.
(mmm savoury snacks, Mon 6 Feb 2012, 8:13, Reply)