They actually charged you the higher rate?
Absolutely ridiculous.

Make sure to file a formal complaint with Choice CS (in Maryland, I think). They aren't the most dependable CS office, but it's better than nothing.
[Edit--I guess you did that via e-mail.]

I would try to figure out who owns the hotel (sometimes they are owned by holding companies with their own corporate offices), too.

Good luck. That's just unfathomable.