Nonsense. When it comes to a for-profit company, there is no such thing as "excessive greed." The entire raison d'être of any such company is to make more money.
The only constraint is that you have to make money without breaking the law. That's it. What's more, for a publicly-held company, the company is failing its fiduciary duty to its shareholders if it is not making every dollar it can.
That said, in the course of making money, most companies also deliver good value to some of the people with whom they do business. It is a customer's job to figure out if they are getting good value, or if they should take our business elsewhere. Companies that successfully convince their customers that they are getting good value, while making money themselves, succeed. Those that don't fail.
It's been said upthread, but RCI's primary customer is not the individual timeshare owner. RCI's primary customer is the developer. Developers bring affiliation agreements. Affiliation agreements bring members. Members bring their exchange business with them, mostly through inertia, but also possibly with intent.
Our goal as informed consumers is simple: does RCI (or, indeed, any exchange company) deliver value, or not? When it does, make use of their services. When it doesn't, don't.
As an added twist, most of us have more than one way to "access" RCI. For example, I have a regular Weeks account, and the Wyndham portal---both paid for out of my annual Wyndham fees. They offer vastly different value propositions. The regular Weeks account does better for "cheap" weeks with low TPU values. The Wydnham portal over-averages; it does very poorly for "cheap" weeks, but better for "expensive" ones. As an example, I recently confirmed a week at Disney's BCV in a 1BR for Food & Wine. That's a primo reservation for those not allergic to the Mouse, one that Disney owners fight for. And, in Weeks, it's ridiculously over-priced at 41 TPU. However, through the Wyndham RCI portal, my total cost was less than $560. After subtracting out the exchange fee and the DVC extortion fee, you'd need a $/TPU ratio of less than $6.75 to beat that in Weeks.
Over time, I expect those sorts of market inefficiencies to continue to disappear. When they do, I'll stop using RCI. But, until they do, I plan on making hay, and I don't care if RCI is "evil" or "greedy". I'm in it for my family's vacations.