You know, I can see where you're coming from. Banning users from playing a game that they bought with their own money over details that can be fictionalized doesn't exactly seem like a customer-friendly business model. Sure, it makes sense for Valve, as they would get more money from you if you open up another Steam account, but it doesn't make sense to ban an entire account over an incident in one game. I haven't really liked this model ever since I learned that Valve sells games as services, not products, which runs counter-intuitive to how I've purchased games since I was four years old.
I'm not a big fan of the Mann-conomy update, either, mainly because it's starting to belie Valve as a customer friendly developer, and one that's starting to develop EA-like tendencies. Not to mention that some of the Polycount upgrades seem more like upgrades rather than sidegrades, creating a system that favors either the lucky or the extremely wealthy. And not to mention the supply crates, which can only be opened with a key that can only be purchased from the store...