Ignoring ratings guidelines is pretty likely to cause issues, which could easily include increased tendency to violence if that's part of the reason for the ratings.
People that are inclined towards violence to start with, I think, are more likely to become more violent with continual or excessive play, but I don't think it's any more of an effect than if they were to continually watch violent movies etc.
For my part, I use them to calm down and relieve stress, knowing full well that they're 'just a game'. Which is another possible issue, where people can't separate fiction from reality, it would probably make them more violent as it was ok to do it here, but not there would become problematic when here is inside a game, but there isn't.
Overall I don't think they do make people more violent, as some studies have pointed out, but I also think it's conditional in that they can be used as a source of inspiration for violently inclined people.
And if we're constantly being told that video games cause violence (thanks media...), there's likely to be some form of bias formed to confirm that as well
Great points you've raised. Yeah I agree, the ratings are there for a reason. I don't know how my brother in law's brain works really.
I play games but never really raged. Sometimes though when my Jungler doesn't come help me, I lose my crap! But playing LOL for so long made me realize that not everyone knows the game or have other priorities.
my brief foray into games like LOL and DOTA made me realise I'm never not going to be a noob at them, and I'm never going to enjoy the game with the regular abuse that noobs get playing them. Similar to my lack of enjoyment of FPS games where there really isn't an environment for social players that doesn't end up getting dominated by non-social players that get their enjoyment picking on and abusing those that are trying to learn to play.
Or maybe I'm just old and jaded...
Play to have fun and not get caught up with name calling and other bs that is the norm in gaming.
I don't really take what people say seriously in online gaming. It's just a person behind a computer after all. When you do, the game becomes less enjoyable.