Event registration on behalf of someone else while logged in

If user is logged into the (Drupal) site, and makes a registration for an event, Civi assumes that the registration is for himself. There are a couple of problems here:

• If the user is actually registering on behalf of someone else and enters in personal details for that other person, the person's original personal details are overwritten by the new details belonging to another person. Understandably, this may not be considered a valid bug, but I will note that at least 2 users on my site have already done this. So it indicates at least that it is not obvious that registering on behalf of someone else would be a problem. I'll also note that our Drupal login sessions do not expire, so users don't think of logging out.

• If the user has registered previously and now he is registering for someone else while logged in, the duplicate registration is not detected - so there is nothing indicating that there is a problem with registering for someone else.