Exp may be part of this, ease of getting into PvP at level 30 is the other portion. This is why I push for the idea of a Ranked version of Frontlines, kicking rights, and ease of reporting.

Sadly, these accounts will get banned, that's not the problem, the problem is what they do to the gameplay in the meantime.

Perhaps they can make a participation rating system that gates rewards on actually providing actions towards the match. (Combat, Objectives, etc.) If so, they should apply it universally to all rewards. I'm much, much more in defense of individual reward scaling based off of performance than I am punishing an entire team for the actions of a few.