Drysc says the high-end arena gear is "intended to always be about on-par with the current tier players are progressing on." That means that if you play well in Arenas, you can earn gear that's just as good as what the hardcore raiders are earning in PvE. But Battleground gear, says Drysc is actually intended to be not as good. Because Arena and raiding take "quite a bit of effort, interaction, etc" (and BGs apparently do not), the gear for regular honor just isn't as good.
I'll let you decide whether that suggestion is true or not, but I've been playing in the BGs, and there are large numbers of players sitting there AFK just to earn honor-- I reported a few of them. That definitely doesn't match up even close to the effort the best teams put into the arenas. But then again, it takes a lot of coordination and effort to lead a winning Horde team through AV, and if I'm able to do that, shouldn't I get rewarded for it? Just because it's easy for some people to exploit the BGs and earn lots of honor doesn't mean Blizzard has to treat all of the people playing in the Battlegrounds like second class citizens. Instead of gimping the gear, how about upping the effort required, and ditching the AFKers?