Who is gating full videos? All I've seen is Patreon as a gratis or else early video releases. I'm not doubting it exists, but it must be in some niche I'm not

Who is gating full videos? All I've seen is Patreon as a gratis or else early video releases. I'm not doubting it exists, but it must be in some niche I'm not aware of. I'm interested to see how that might work.