Comment by JohnMakin

For me specifically, I do believe this is a major part of it. However, if my options are to use a VPN or the service, but not both, I'm more inclined to pick the VPN and say screw the service, I just will opt out of using it. There's no real reason that a sufficiently sophisticated network/security team at a large company can't differentiate between commercial VPN users and "bot" traffic. It's just laziness/incompetence. Sufficiently advanced bots use residential proxies anyway and it really isn't difficult to go down that road.