OK and a goup of gamming teens are worried about the TOS, how could it be enforced? I know a few guys that play on an account and their son plays on it also. It's against the TOS, right?
Pretty easily actually. IP 1 from Texas signs on and plays the game then signs off. A hour later IP 2 signs on from Virginia and plays. Flag is sent to HTC due to the time frame between logins associated with the IP address. IP 2 is still logged in and IP 3 attempts to login from California. Flag is again sent to HTC for multiple IPs trying to connect to the account at the same time. If this was being abused between 5-10 people, over time there will be enough information to conclude that the account was being shared.
This is just one simple way, of the many, that it could be done.
Keep in mind that HTC reserves the right to terminate any account at any time. It's up to the account holder read the TOS. After all, they are agreeing to it when they sign up.