My personal opinion on this is that anyone caught using an account created by another should be instantly and permanently banned. This is regardless of whether the account was hijacked or "legitimately" purchased. If this is the account of a famous content creator this becomes just about the worst fraud that can be perpetrated inside of SL.
However - there are a number of industries now whose intentories and controls are in the form of a person. If there were a mechanism by which an account could be transferred that made it instantly clear that it is no longer the same person, I'd be ok with that. Something like the account name now says Ansche ChungINCORPORATED, or Chip MidnightTRANSFERRED. That way you would know not to expect the exact same service you received previously.