if the instances stopping some from buying everything up can be bypassed by just having more money then they're pointless. maybe one guy can't have so much property, but what about a firm? and then a second firm, so many companies that own so much all owned by one person

Only countries where the local rich or the government bought up enough that when the real capitol arrived, they said "not for sale"

Oh yeah, and also had a military strong enough to make it too risky to send in the private armies that companies used to have