AB exploit question

Recently in Arathi Basin matches I've seen players, both Alliance and Horde, on top of the stables roof.

It doesn't appear that there's anything usable nearby to jump onto to give a boost, but I think I've seen people getting on top of the outhouse first. However, in the heat of battle, I can't tell if they're doing it legitimately or by clipping on the side of the outhouse.

Is this reportable as an exploit? Or is it intended? I just want to know if I should start ticketing the jokers that do it. Once a frost mage gets up there it takes a lot of manpower to dislodge him.

edit: I want to clarify the people on the roof aren't just standing there - they're shooting down on us poor melee that can't get up there to stop them.