If you have friends staying at a particular resort and you are their guests, I don't think it would be a problem. The only place you might run into this as an issue is at YC/BC. I have seen them check IDs and ask people to leave, there. But, I don't think you would have a problem at CBR.
About 10 years or so, Disney advertised that you could swim at any of the pools but some have become so popular that they discontinued that... it was right about the time they added many new rooms with the introduction of the Value Resorts and Coronado Springs.