You can sue the hotel, though you should also probably name any managers whose names you know personally as well. The hotel has no right to keep more of your money than you agreed to pay for the room; if they take more they are at a minimum in breach of contract, which provides grounds for a lawsuit--and possibly they have committed consummer fraud by engaging in an unconscionable commercial practice or even, if they are keeping money they know they are not entitled to, theft. (If consummer fraud or theft, you may be entitled to more than the actual amount of the overcharge--e.g. additonal damages or compensation, or possibly attorneys fees.)