It's marketing that causes most of the problematic sentiment which people get caught up in. It is, after all, a highly competitive market and manufacturer's sell on a "this is better than that" basis. If we each didn't believe that about our chosen brand, we wouldn't be buying the cameras we do. For some people, this kind of brainwashing spills over into an all consuming mission of destruction against anything perceieved as a slur or competition against their chosen brand/tribe. It is tribalism at its worst and the relative anonymity of the internet makes it worse. Put a load of different brand owners in a real room, and the brand rivalry will climb no higher than playful banter. Put the same people in an internet forum, and they can end up wanting to kill each other! Perhaps we can call it net-rage. To prove my point that marketing is responsible, if you take it out of the equation, the rage vanishes. Try classic/vintage camera brand forums where people are discussing cameras long abandoned by competing manufacturers, and you will generally find pleasant people all getting along fine and happy to help one another.

Marketing is designed to conjur up selfish feelings, irrespective of the fallout. As anyone in the business will tell you, "You" is the most important word in advertising.

Sorry examiner, I wandered off the questions a bit there.