Of course they can, if a game is designed that way.
But a game does not HAVE to be designed that way, just because it COULD be designed that way. Blizzard does not HAVE to use your theoretical alternate design, just because they cannot prove TO YOU that they shouldn’t.
Blizzard’s decisions do not need YOUR approval, or 1 million other players’ approval.
BUT if the argument is about SHOULD, then I’m on your side – I like your idea.