One person roping you (or even multiple people for that matter) doesn't mean that we "do nothing". It just means that people are rude and do it. Of course the more matches you play, the more people you'll run into with a bad attitude. People do this kind of thing on every game ever.
Rest assured that we do take action on accounts that are repeatedly reported for roping. Just because you don't see it, or experience it from multiple people, doesn't mean that we don't take it seriously! Report the player so we can look into taking action.