No, advertising unlimited and then complaining when someone truly does use unlimited is not a problem with my mindset, it's a problem with the person who runs the service, if you don't want people to truly use unlimited, don't advertise unlimited.
You must be living in a bubble if you think that's how companies operate.
Saying that someone is an asshole for using an API in a way which clearly should be possible according to the documentation is a very clear sign of that person being a junior developer who don't have actual real world experience of anything except toy projects. Any developer with some years of experience would understand that this would happen and he should not be surprised over it.
It's very possible that no one involved in this is even aware of this issue, so automatically calling them assholes is somewhat incompetent at best.