Yeah I was surprised to learn this. I don't know if this is something that can change or not. In the grand scheme of things I guess it's not a huge issue as on most platforms the initial traffic and money comes early on as well although it is nice to have it recurring forever regardless how small.
Someone mentioned it's because there would be inflation essentially if this wasn't the case and that kinda makes sense to me. I think someone also mentioned it would keep the biggest people growing and not give others a chance so I sort of understand why this is the case.