What exactly is "Verbal Abuse" and "Offensive Language"?

So I've been going a couple games with some friends and we've been put with stupid people in a few of them. (No, I did not call these people stupid to their faces.) But two of my friends made comments on how the person is feeding and refuses to work with the team. After the game, they got chat bans for "verbal abuse". Here's the thing, they didn't swear, they didn't degrade them for no reason either. My friend originally was trying to help the person understand how to use his ult, but the person didn't listen and kept on making the losing game even harder for the whole team. I think it's bs that people get banned over petty things and people don't get banned when they should. I can't tell you how many people have used the words "%%%%%","nigge*", and "cun*" WHICH ARE OFFENSIVE WORDS. Of course those aren't the only words they use, but those are just some. Before anyone starts saying that "everyone uses them", I don't. I've never used those words in my life. And I'm tired of seeing them in every game, they're degrading. I think if you're gonna ban someone for getting mad at another player because the player REFUSES TO WORK WITH THE TEAM/TEAMMATE then I think you should ban people for real reasons too.