Tell that the people on the servers, being more active in chat by flaming each other than being playing the game :/
I don't know why but some people even take public games super-serious and get mad very fast. Number 1 reason for the madness is that they get shot, could do better and get frustrated. I would not wonder if some of them are interested in glitches/cheats or similar, but I don't really care. I play my game and if others think they have to gain an unfair advantage, they can go ahead, the game is not personal enough to make me care about a few jerks of 100 players. I don't want to lead this thread into a different discussion, but the atmosphere on the servers is usually everything else than relaxed, because a bunch of people unfortunately is always mad about something, that's the way bigger issue.
Also I have to say that I feel a bit bad for being forced to play on a mix of low and medium settings. It has been a while since I played on my decent desktop pc where I was able to play at high settings, but I think on low/medium it's definitely a bit easier to see the enemy sometimes on short to midrange. I'm using a quite low resolution as well though and on long range I only see a very very tiny dot, which does not look like an enemy at all and I remember it was very hard to get used to that. So I'm just hoping I don't have any kind of advantage, my skill did not exponentially improve since I had to switch to low settings at least.
But what should be kept in mind is that there are a lot of players on the server, probably everyone with different settings, different screen, different equipment. There just won't be the 100% amount of fairness. That's something you just have to accept and deal with. Therefore I don't mind what others are doing, because it is a game and my fun does not get reduced by some graphic adjustment some people might intentionally use to have an advantage. THis won't make them doing much better. In the end it's the personal skill that makes you a good or bad player and not situational advantages causing one kill more in the list.