If I understand the situation correctly, I'd say it's completely legal.
Hams have actually been doing this for many decades in the form of "club membership" requirements.
There are many ham clubs that have permanent stations set up and they don't charge hams to pass traffic on them, or by the hour to use the equipment. But, you must be a club member to gain access to the equipment, and that might be $1000 a year, or whatever they decide it will be. If you don't like it, don't join the club!
There are remote controlled HF stations on the air like this, and have been for decades.
When "autopatch" was popular on VHF-UHF repeaters, although some repeater owners allowed open access to those, they were never required to do so. Many systems were owned by clubs, and if you wanted to use the autopatch, you had to join the club. And membership dues could be whatever they wanted to charge. Nobody was forced to join a club or use the autopatch, or use the repeater. But if they wanted use of the hardware, they had to be a club member.
To me, all these scenarios are very similar and have been going on for a really long time. I can't recall any being deemed nor judged unlawful.