I bought two copies of Spine during the original kickstarter. I'm a programmer, not an artist, so my intention was to have a second copy available for any artist I happen to be working with since it varies by game (since I'm indie). Keep in mind I never intended to use more than one artist at a time. However, looking at the current licensing it seems this is impossible since I need to have a permanent user. This is very limiting as I don't intend on buying a new license every single time I work on a new game.
The enterprise licencing scheme is even more problematic, and makes little sense. You can only license Spine to a user, but you're charging "companies" enterprise fees that make $500,000 or more in profit? That is contradictory, and it seems using spine at all for non personal projects falls into a legal grey area.