Well, by the time you've conquered southern Italy and all of Sicily and built farms, roads and ports there is so much money coming in that you have to give tens of thousands away each turn to stop your family members becoming even more retarded that they already generally are. I usually use it to fund the Makedonians, and to a lesser extent KH and Epeiros so that no single faction unites the entire Greek peninsula... Those guys are a real nightmare to conquer with Polybian legions when they have those chainmail hoplites and elite phalanxes.
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