Agree that these 'statements' are a pure riddy, and their inability or unwillingness to understand that their actions have consequences is pretty annoying.
But we've also got to remember they're daft teenagers, so telling them to stay away is going too far, IMO. If they were adults, I would agree, but they're still young and immature, and I'd be surprised if you didn't say or do anything in your teens that you now look back on and cringe. If you didn't, I suspect you're in a very small minority. Probably in 10 years time most of them will look back and realise they were being wee dicks, so if we alienate them now we may lose some who would otherwise mature with time into die-hard, law-abiding fans.
Of course I'm not talking about indulging them, obviously they need to learn how to behave. The club needs to keep handing out bans when they think it's necessary. Sure, we'll lose some of them along the way before their baws drop, but they're probably not the ones who would be in it for the long term anyway. But I also don't think we should be alienating them completely. Educate rather than exclude, but continue to hand out bans to the ones who can't or won't accept that violent, aggressive and intimidating behaviour is simply not acceptable.