A friend of mine is a parole agent, and he talks to some pretty crazy people at work that are violent and unstable, and part of his job is telling them the are getting a parole violation and going to jail. Needless to say, this is sure to not go over well with people that are already unstable and violent, yet he rarely gets in altercations with the parolees. His secret-it's in the delivery. He can tell people precisely what they don't want to hear so long as he delivers the message well.
I tell this story because I think the root cause of the occasional conflict here isn't that people have differing brewing practices, but that the delivery of certain messages is flawed.
You can be as right as rain on a subject, but if you come across as a jerk while doing it, you probably won't be received well.