Cheating is wrong, and it shouldn't happen. One clue: the negative connotation of the word "cheating" itself.
Yes, some people cheat. That's a fact. How many? You and I will never know, because it's generally considered a shameful act, so people are reluctant to admit it.
Also, some people lie, steal, murder, rape, and all kinds of other bad things. Those actions are also wrong, and shouldn't happen. They do happen, but that doesn't make them good or acceptable.
Saying that bad things are perfectly natural is one thing. Saying that they are acceptable is wrong.