We stayed at BWI in December and had to call and request one. We stayed at WL in January and had to call and request one--if you have to request a frig, it is first come, first serve, especially at WL. We noted it on our ressie, but since they do not know your room number until you check in, it is not delivered until then. I have seen several posts where they ran out of them at WL, and folks had to wait. Hopefully they will be permanent soon, if not already.
BTW: still not free at the value resorts. It's $10 a day.