If there is a charge, then we must have brought our own towels. I sort of remember having a locker. So we must have put our towels in the locker, until we were ready to leave.
There's more than enough to do there for a full day. You have to remember that there are lines at the water parks, too. There are lots of things to do thre, especially at BB. I personally love spending a day there, if not 3/4 of a day, but only if I have time to get away from the main theme parks.