The parents are the ones that pay you so maybe that is where
the deal can be made. Make it so the parents can oversee the kid's progress without actually knowing the answers or doing any work. A cheaper tutor.
I believe you are correct, however, in that things will shift when it is "anonymous" and online. Kind of like selling childrens' toys: the kids have to like it, but the parents have to be willing to pay as well.