Somehow, any outdoors-related forum can easily become a breeding ground of wild ideas, extreme beliefs, or uninformed notions of what you should or shouldn't do outdoors. This site seems to manage to avoid a lot of that nonsense, thankfully.
I haven't been banned form other sites, but I've come close. Probably the closest was on a gear site where I just had to take issue with some rather extreme beliefs about choosing knives more for self-defense purposes than outdoor usefulness, extreme outdoor survival, bug-out and living-in-the-woods scenarios, etc. Don't try to tell anyone with a bug out bag why they don't need it. Trust me, that argument doesn't end peacefully.
In a lot of these cases, it doesn't matter who is right or wrong. It's popular opinion that wins, and if things get ugly the dissenting opinion will be seen as the one that instigated the argument. Thus leading to a ban (or a reprimand from a site admin).