You agreed to be paid half the lesson fee almost a year ago. You have had plenty of time to remedy that situation, so I am confused as to why this bothers you now...other than perhaps you feel you are letting someone use you...but that is your issue to deal with, not the BO's.
Reading your more recent posts, that sounds like the entire issue...that you feel you are being used and underapreciated...but that is not the BOs problem if you have never brought it up. I think you are venting about the BO (who may well be an ass, who knows) whereas the issue may be more that you have trouble with negotiation/confrontation.
To recap: what your BO is doing sounds like smart business, you just have to change your reactions so that you are also operating in a business like way.