Two things...
1) Peoples' "differences of opinion" have almost always revolved around tangible goods, like land, resources, the right to do some activity, etc.
2) As such, the winner always gains something from winning. They gain the land, resource, right to do whatever they wanted, etc.
War is always about control...be it control of land, resources, people, whatever. Control is power. Control of money, people, etc is power.