This is true, you are not supposed to use the pools at other resorts, although in some cases you are allowed to use other facilities at other resorts, such as the health club, spa, etc. One little tidbit- the spa and fitness center at the Disney Institute are still open, and I was even allowed to use them as a guest of an off-site resort. The fitness center here is one of the fanciest on property, with separate whirlpools and saunas in the men's and women's locker rooms, towel services (even chilled towels LOL) and various free toiletries laying about. I believe it's 15 dollars for one day, or 35 for length of stay. If you are a Disney resort guest, just show your resort ID at the gate, or if you're staying offsite, just tell them you want to visit the fitness center and show another ID. (As a side note, although technically you're probably not supposed to do this, you could probably get into CSR with your All-stars resort ID to use the fitness center at that resort, and end up using the pool there as well ...oops did I say that? They would have a hard time telling you you had to get out of the pool if you had purchased a fitness center membership there anyway.)