I've always heard it referred to as infringement, in a legal context. I'm sure game publishers (and music, film, etc.) would like to equate it in the public mind with common theft of physical goods, but it's all just propaganda.
We're just playing games with words at this point. The law is pretty clear, that distributing a copyrighted work such as a copy of a video game is illegal. I don't know why people like to repeat this line, that "if buying a game isn't owning then piracy isn't theft." Maybe it is a moral/ethical argument? It's not going to help you in court.
Given what happened to freelancer, I think the only way you should give Chris Roberts your money is if he agrees to lead the project for two years, then quit and hand it over to someone who can actually finish it.