As to whether Disney is actually cheating on controlling rooms for rental (e.g., such as renting out more than it has a right to do so), you really cannot determine without a full examination of the books accounting for exchanges, rentals of rooms. You are entitled to review accounting documents for the DVD portion of a resort but must call to request what you want to see and then make a visit to DVD's office to actually review anything.
As to whether we are legally to an extent subsidizing the rentals, the answer is yes:
DVD keeps a certain percentage of the ownership of the resort rooms/reservation time, 2% to 4% of the resort even when sold out. It can rent the time represented by its retained ownership interest. It also, as mentioned above, can rent time equivalent to points traded out. For both of those events DVD does not actually pay dues. It can also rent unreserved DVC rooms at 60 days or less out (called the "breakage" period). As to those breakage period rentals, DVD also does not pay dues but, after actual costs to DVD in doing the rental, the proceeds go to offset dues up to 2.5% of the annual operating budget for a resort; anything over the 2.5 goes to DVD entities.
The estimated annual dues per point are determined by including Disney's share of ownership. However, Disney does not actually pay its share, other than property tax when they actually become due, unless the amount paid by members is insufficient to cover all costs and amounts designated for reserves for the year. It can do that because it chooses each year to guarantee that it will cover costs in excess of the estimated dues paid by members and thus agrees not to have any special assessment (subject to certain disaster exceptions). Under the law, that choice allows it to avoid direct payment of dues for the year. It could ultimately end up paying some amounts but that just depends on whether the dues paid by members are insufficient to cover costs for the year. A lot of foreclosures resulting from lack of payment including of dues would likely be something that could result in Disney actually covering some costs in excess of dues collected at a sold out resort.
Thus, when DVD rents out its share of ownership, your dues are likely covering costs usually paid out of dues for the room, such as electrical costs that include those for the room but not daily made service. Moreover, when it rents rooms as a result of a trade-out or for the breakage period, the same member-usual costs are being covered by your dues. However, it bears the cost of doing rentals and bears the risk of not renting a room (which for the last two years or more has probably been a significant risk).
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