Yes, sometimes this is definitely a scam. This is why we have a general policy not to transfer items or stats between avatars, and also because we have no way of knowing if two accounts are really alts. Even if it is their alt, it's possible they were banned for violating terms and then made a new account. We have the ability to deactivate items, so if we believe an account really has been compromised, we could deactivate the items on that account and forward them to another account if we wanted to. We don't usually do this, though, for the reasons stated above.
I'd be interested to hear about the experience of anyone who has experienced their account being compromised first hand, or come across a credible report, and how it was handled.