Every person and company I know who had an Adsense account was banned and not paid. Two of them were banned for terms violations which were things Google reps told them to do. Endless conspiracy theories on this, no idea.

I am guessing these companies were not big enough to make enough of a fuss and have a good legal team? Google likes making money, and if there is the slightest reason to not have to pay someone, then they are gonna make use of that reason. Might even make it onto someone's KPI list of "prevented fraud".