To answer myself, I'd guess once I got home, and pulled up the mailed/emailed copy of my reservation, I could submit that the hotel and HOPE to get reimbursed for the difference.

That's not a guarantee though, the price at return time for a car rental didn't match the price I was supposed to receive. I didn't worry about it, figuring I could easily take care of it from home. I got such a run around from the rental office that I don't think I ever got the difference credited back. It's definitely preferrable to getting the rate corrected up front, and not hoping you can get a credit after the fact.

Jeff