People get upset about "causal" noobs like my self getting gear with in equal item level to their life draining BT/Sunwell loot. With out the massive time investment.The thing they don't get is that we invest almost as much time as they do. (in the cases of the people going to these comps likely more -I saw a MGL vid where they mentioned playing around 50 hours a week)

Cool thing is I can fit PVP/BGs/Arena around my life. I've done the extreme raiding thing - it doesn't fit in the an active life style and full time employment (talking about AQ40/Naxx clearing guilds when it first came out)

The other part they get upset about is the small class balances that get introduced for PVP that might effect PVE. Though I can't think of one serious one that made it past the test servers.

Oh and the last reason is that they aren't good at arenas.

But mostly it is the gear. People deny it but a big reason they raid is for epics as those epics make them "better" then others in game. IMO just remove the loot system - make everything purple or grey, would stop these losers getting so hung up on it.