Cause they're knuckledraggin neckbeards. Being 32 ia only effective if the damn area is 32. I see people in Crucible in full crota gear, and I love the opportunity to wreck em when I can, I do have the full set and can be 32, but those aren't PvP perks. The best are on vendor gear, they will have the perks and stats you need. And for those that think that crota can only be done with 32s, they're equally dumb. I've watched many kick ass videos of solid teams with guys as low as 30 on hard mode gettin it done. My normal team has 2-3 31s as well, and I don't mind helping teams with those levels either. Just ignore them.