Re: Where does the money go?
We just published our income and expenses (for the local dojo) in our newsletter, so I can be pretty confident about what they are.
We are a non-profit and don't pay the instructors. Expenses are primarily rent, then telephone, supplies, and publicity. For seminars we pay airfare and hotel accomodations but the sensei who offers our seminars normally turns down his appearance fee.
We tend to make a small amount of money at each seminar, which goes into reserve to cover the months when we otherwise wouldn't make enough to pay the bills (December is a particular problem). Last year we did not quite break even, but we have reason to think we may this year, and the deficit was less than $100. Eventually the tatami will wear out, though, and then we're going to be in for it--we'll probably have to ask the students for donations. (There's a plaque commemorating the people who funded this set of tatami, many years ago now.)
It is non-trivial keeping a dojo in the black. We left our previous location in part because the rent was slowly killing us.
I won't say this is the only reasonable model for a dojo. I would willingly pay an instructor, though I'm grateful that we don't have to (because, frankly, I'm not sure we could do so and stay afloat). But it seems to me that even a dojo which pays its instructors should be willing and able to account for where the money is going. (Don't forget taxes, especially if it is for-profit; they can be steep.)
International dues at my level are $30 to join and $10/year thereafter. I figure this pays for record-keeping plus having the HQ dojo as a resource to teach my teachers; in any case it's not much money.