When people play from cafe accounts and do something those accounts get banned. If someone uses an admins computer and abuses the admin is responsible. So why should it be different for anyone else? Admins can make decisions as to how to ban a given player via ip or steam id.

So in summery:

The abuse in question was;
if an admin can ban from IP: Yes they can
if an admin can ban an account or ip that was being used by a player other than the owner of said account or IP: Yes they can

Therefore no abuse has been found to have taken place within this submission. I will also note that the user who submitted this abuse report was banned and never filled a valid Unban Request for this banning; thus it should be observed that the Admins right to ban this user was at no point brought into question for this banning. As a result no investigation as to the validity of this ban was or shall be launched. Only the right of the admin to ban the IP or ID that is being used by a person other than the owner of such addresses was brought into question in this report.