It had nothing to do with skins kiddo. Its the integrity of Valves investment.
Lets pretend for 10 minutes that in another alternate universe you were smart enough to own the rights to a sport (NFL, FIFA, etc). Now lets say that during breakfast, while counting stacks of hundred dollar bills, someone tells you that some team, that you were kind enough to let play in your game, LIVE OFF OF YOUR CREATION, decided to try and get one over your head, because playing video games for a living isn't dope enough. Now, if you don't do something about this, it sends a message to people that it's OK to do. And you don't want that, because if it becomes known that your sport is rigged, it no longer becomes fun to watch, and you don't make money.
So what do you do? You make an example of the kids that were stupid enough to destroy their careers for some pixels. And the joke's on them, because you don't give two shits about the money that was stolen or their careers, you care about the MILLIONS of dollars you stand to lose if it continues.
Did that make it through your thick skull?