when your opponent asks for a draw when they are clearly losing


Such people are clearly jerks and every game that attracts many includes some jerks. It's been my experience that I've seen a smaller percentage of jerks in chess than in other competitive endeavors.
There should be some extra penalty for frequently letting a lot of time run out on one move in terms of how much you are allowed to play. Don't subtract extra rating points because that will pull down the overall ratings of all due to less points for wins against that player than the winner deserves, etc.