I think what you are asking about is a fee apart from the RCI points membership fee. Most resorts don't charge these although a few do. I think most of the resorts that do are older independent resorts. I have seen it with a few VRI managed resorts. I have owned Vacation Village properties for several years and have never been charged anything over the RCI points membership renewal fees.
Yes tschwa2, you hit the nail on the head.
As a backdrop, My membership ends on Feb 28, 2019, and so I need to renew. I figured I'd renew for 5 years, save a few bucks. Computer wouldn't let me. I could only do 4 because the "Membership Term Expiration Date" was February 28, 2023. Five years would put it out beyond February 28, 2023. So I called RCI. Apparently it can only be renewed in 3 year increments, and the expiration date can be no more than 5 years out, according to a "Vacation Guide". They can't extend it by a single year to allow me to do a 5 year renewal. The "guide" at first told me it was due to policy. I asked her where can I see the policy. Answer: terms and conditions at the bottom of the page.
While we're talking, I read the document and noticed that it did not contain any provisions of that nature, and told her I had caught her in a lie or misstatement. She said she assumed it was in there, so it must be in a contract with VV. "Can I see that?" "I don't have it." "how do you know it's in a contract then?" "It's the policy" You get the idea. Anyhow it was clear that it was probably something to do with VV.
I then read some prior posts, 5 or so years old, that I interpreted to imply that the expiration terms were such so that a fee would or could be imposed to keep a unit in the points system (above and beyond membership and transaction fees).
That all said, having the terms of the "Membership Term Expiration Date" be based upon a Resort's policy makes no sense either. What if I had two units, one with VV and one with Wyndham (or Holiday Inn, or any other Group)? Some of these policies and how they address issues makes no sense.