Confused about pvp gear scaling

Tried some random bgs the other day and was just getting absolutely trucked, have a few questions on pvp gear scaling.

1. I was on an alt, with pretty much leveling greens on, but when I entered a bg my gear would say (360) / 450 or something like that. That means my gear's getting scaled to 450 right? In which case what is the point of all that honor gear that scales to 450? Is there any benefit?
2. I was checking details, and noticed that classes with the exact same spec, were doing around 120% more damage. Is that because I was getting scaled to 450 but many people in random bgs are scaled much higher? I could have sworn one of the characters I looked at had a pvp set on that was all rares, so I'm just wondering if once again if the honor set does something over getting automatically scaled to the same level.