Zebras occupy eastern part of the Old World because of savannah on the Cutiemap at the west from Equestria and, well “Fallout: Equestria” where they are used as China. They are rather unstable feudal empire where small tribes live by the old ways under protection of mighty kings who have actual armies.
Zebrican arts of enchanting are tricky and their results are unstable, so properly crafted battle golem is as expensive, as mighty and obedient. Though, the source their obedience is intelligence of a foal, so if the golems are left alone, they can easily crumble just from fear and uncertainity.