When banter goes wrong

A bit off topic (ever so slighly) but is anyone else sick of certain individuals who hide behind their keyboard calling us 'cretins' and belittle everything we say just because they happen to disagree with it?
I understand these boards are heavy with banter and of course that's fun and I can give as good as I can get and maybe i'm naive, but i'd like to think that these boards are trying to replicate the kind of banter you'd get at a game or in the pub talking with your mates.
If I said something at the pub like 'we should buy Modric', if someone disagreed with it they'd say something like 'nah mate, he's awful/overrated/spurs reject etc' and we'd laugh it off and just move onto another topic or if debate was needed we'd just keep talking until we were bored. On here certain individuals would darken the tone with a 'you absolute cretin, you know nothing about football etc etc etc'
Now 99% of the topics discussed here are conducted in civil ways and i'm certain that the regular people on here appreciate that and it contributes to the success of this site which we're so very thankful for after the demise of the BBC one in 2011 but certain individuals almost go out of their way to act like bullies and talk to us in ways that they never would in real life.

I just think it's very immature to hide behind your anonymity and use such strong language to shoot down certain ideas when you could exercise better control and just realise that 1) we're supporters of the same club and 2) opinions are just that. Everyone has them and if you disagree then take a deep breath, realise that... guess what? Life is too short to be so angry with everything and most of us come on here to have a light hearted look at how United (and other clubs) are being run on a day to day basis.

You may think you're being intellectual in the ways you belittle others but all that's happening is that other members on these boards see your names and even before they know what you've written assume it's going to be a load of negative and unnecessary vitriol.

Rant over.