Steam user violates subscriber agreement, loses $1,800 in games
Found on Ars Technica on Sunday, 13 March 2011

The user in question, who has a total of $1,794.52 worth of games on his or her Steam account, decided to ask how much another person might pay for such an account.
That was a month ago. A little more than a week ago the user was unable to connect with Steam, and was later informed that the account had been disabled for violating the Steam Subscriber Agreement.
Valve has since posted on its forum that the account has been re-activated.
That's why it's better to buy games on CD. It is obvious that companies like Valve hate it that consumers are allowed to sell their used CD's because they imagine there's a "lost sale". Having control over the games allows them to bully the users by claiming that some TOS was violated; a TOS which would probably not withstand a test in front of a court. It's pretty much as if they storm into your house and take your CD's away because you put them up for sale.