Tigger wasn't a water cat, but he sure didn't mind hopping in the tub now and then, as long as water wasn't actively running. In addition to being a nice cool spot to lie down on during warm months, it made for a nice hiding place for an ambush.
It's time. Besides, it's not like they're being melted down. Instead, they're no longer going to be officially honored by a city where a large number of people believe, with damn good reason, that they shouldn't be.