Other Groups

Some people don't fall into simple groups such as the Empire or the Republic.  These are some of the other 'groups' people may be a part of, but are not the only kind.

Mercenaries
-They sell their services as soldiers out to the highest bidder, either as groups or running lone-wolf.  They're not shown a lot of respect, and seen as not showing any loyalty or respect to anyone.

Transporters
-Shipping food, supplies, wares, Zoids, or occasionally even people over great distances, the Gustav is the Zoid of choice for most transporters because of its excellent ability to haul heavy loads.  Some even go into business as merchants, transporting their own wares.

There are of course many other kinds of people.  Thieves, gangs, assassins... generally not decent, law-abiding citizens, but there are exceptions to his.  Some people just choose the path of a wanderer.