Its not really cheating, it's just sort of cheap and I'll admit I do it sometimes. Why? Because it gives you an advantage in the game (and it takes less skill).
When gamers find an advantage in a game (in shooters it's usually camping, or the best gun like how rigged Model was earlier) they exploit it because it maximizes results, that's just how it is.
Anyways, killing campers isn't hard. They give you a replay of how you died to show you exactly where they are, than you pretty much have the advantage. Use flashers, stunners, grenades, noob tubes, whatever...