Maybe the MEC has a limited budget and spent all their money on the tanks and helicopters, so they had to rip off the pods on a helicoper for an artillery piece.
This is a vehicle for the civilians, not the MEC. Also, with "maybe"s we can reach everywhere. Maybe the MEC invaded Switzerland and robbed the Swiss bank, so they bought a series of BM-21 MLRS's from Russia?
As Jimi said, lets move on and discuss something else.
This HUD looks epic:
Oh, and, dont tell this to anyone, but, I know they are making a huge map with huge runways.. and an AC-130