some people might do it, but if someone doesnt like pvp or doesnt wanna do it i wouldnt force him.
actually in the guild im in, me and my arena partner (our guilds druid) are amongst the only ones who do some arena next too it.
we dont really do this too gear up for PvE, but both of us have been picking our pvp pieces too fill up non epic slots.
i actually had a guildie whispering me i should be using less pvp items, but the silly idiot doesnt realize i havent seen anything usefull drop that could take the pvp items their place.