The idea that I could have an account with hundreds of games I purchased be taken away from me without reason, or without recourse is absurd. Facebook, or really anything holding licensed content needs to be regulated.
If you get banned from the Steam community for spamming/harassing/being awful your game library is still there. Even if you get banned for cheating in a game, you only lose access to that game and not the rest of your library.
I lost full access to my account when a friend gifted me a CD key he bought from someone on Ebay. I think it was originally bought with a stolen credit card, so a chargeback was issued, which then meant my whole account was locked out.
Support did restore it, eventually. I got the impression it was a one time mercy. This was back in 2010 so their policies may have changed.
"This account has been disabled as a gift subscription that you recently accepted in your account has been reported as fraudulent. The subscription has been removed. We will make an exception in your case and reactivate the account at this time. Please refrain from accepting Steam gifts from unknown sources in the future."
Putting risk on buyers of "stolen goods" is normal, so I wasn't upset at Steam for that part. But having the entire account impacted is another story.
As @asymptotically3 said, community banning doesn't take away your games, and in-game banning only blocks you from that specific game's multiplayer. In the past you could risk account suspension if you chargebacked purchases or redeemed stolen keys, but even that got changed years ago to just remove the specific game/license from your account instead.
Only large-scale fraud would get you banned, and even then I doubt they would disable your account entirely and not just disable future purchasing.
