I'm not doubting what you are saying, it sounds logical to me. Is that a law that governs timeshares or condos? If that's true, where will the money come from to cover construction? Liftblog.com estimates that the cost of this system is around $300 Million. That is a ton of money. They have to get that back somehow. Now we see why they are charging for parking. A bus is around $500K so they are really making a huge investment in this system. The size and location is also very logical. The Mod on the Rumors Gondola thread stated that there is almost 10,000 rooms that will be served by the system and 2 parks. That makes sense for this system.
This is mostly basic condominium law which is also applicable to the timeshares. The only Disney entity that can actually charge you annual dues is the association (which essentially includes DVCMC, the Disney entity to which the association has essentially transfered its day to day running of the particular resort) that is responsible for the particular condominium site. It can charge you annual dues for the operations at the site, for the maintence and repair of any common elements at the site, for all service agreements it has with other entities to provide services to the owners of the site and for any taxes concerning the site. It can set up an operations budget and a capital improvements budget.
What it cannot do is charge members annual dues for the construction of anything that is constructed offsite and not owned by the members. For example, it cannot charge you dues, or even enter into contracts that would have members paying Disney for the construction costs of Toy Story Land. Likewise, any particular DVC resort cannot be charge for the construction or operation of transportation systems not providing services directly to and from the DVC resort. In other words, no matter what, the owner/members of all the existing DVC resorts at WDW cannot be charged for even the future operation of the gondola system currently being constructed because it is not going to serve any already existing DVC resort.
The gondola system is being built by a Disney entity other than the association or DVCMC, most likely Walt Disney Parks and Resorts (WPDR) which among other things, is responsible for WDW transportation systems. WPDR owns the transportation systems and to the extent any part of those systems actually are built on any property owned by a DVC resort, it will have an easement to enter and use such property to do such construction and the transpotation-related improvements it builds on any such DVC site will actually be owned and maintained by it, not the DVC resort.
WPDR cannot legally charge any existing members any annual dues at all, much less any for the construction of the gondola system. The only way it can get any portion of the annual dues to cover any transportation costs applicable to any DVC resorts is through service contracts it enters into with the applicable DVC resort association, which then charges members annual dues that include the agreed to transportaion-related costs. It currently has no agreement with any existing DVC association that relates to the gondola system. As to the current gondola system being built, it will never have any service contract with any existing DVC resort because that particular system will not provide transportation to and from any existing DVC resort. It may in the future have a service agreement with the DVC association that is eventually set up for Riviera because Riviera will be a direct user of the system. However, that association once established will not be allowed to enter into any contract that would have Riviera members charged specific dues to pay WDPR for the construction costs it has incurred for the gondola system.
So how does WPDR recoup the $300 million for building it (a sum you assert is a ton of money but actually is not in relation to Disney's worth, revenue or net income). It will do so the same way it recovers the costs of purchasing new buses, new boats, or constructs improvements to the monorail. It will have service contracts with the associations of the DVC resorts that use the system, which charge fees to the applicable DVC resort to cover its proportion of all the transportation costs of the resorts using the system. The fee will likely factor in a some amount annually for construction of the system, and thus WPDR will eventually recover much of the building costs over a long period of time through transportation fees charged Riviera and rental charges for rooms made at the other Disney resorts that use the system, and hopefully the additon of the system will also lead to more rentals at the applicable resorts, more use of the parks, and to a reduction in other transportation costs such as the buses.