With online MG, especially if you are sending $ overseas...they WILL call you before they approve the transaction, and if the receiver's name has been used a bunch from people all over the world, their name is flagged in MG system. So, when they call you they'll ask "so who are you sending money to and why" and if the receiver's name has indeed been flagged they will say something to you like "are you aware that you're engaging in illegal activity with this person" or something like that and that's when you hang up the phone and get a bit freaked out Lol....now your "name" has been flagged by MG as well.
^^ This does not happen every time, BUT it is much more likely to happen than in person
When you go in person, you can give a fake name and they do not ask you for ID, who you are sending it to and why....none of that. Online is MUCH more traceable than in-person...if you're worried about that sort of thing.