"The reason that the rich were so rich, Vimes reasoned, was because they managed to spend less money.From Terry Pratchett's Men At Arms.
"Take boots, for example. He earned thirty-eight dollars a month plus allowances. A really good pair of leather boots cost fifty dollars. But an affordable pair of boots, which were sort of OK for a season or two and then leaked like hell when the cardboard gave out, cost about ten dollars. Those were the kind of boots Vimes always bought and wore until the soles were so thin that he could tell where he was in Ankh-Morpork on a foggy night by the feel of the cobbles.
"But the thing was that good boots lasted for years and years. A man who could afford fifty dollars had a pair of boots that'd still be keeping his feet dry in ten years' time, while a poor man who could only afford cheap boots would have spent a hundred dollars on boots in the same time and would still have wet feet."
It's always wise to listen to the comedians and satirists. They usually tell the Truth well in a few memorable lines, as opposed to Serious Thinkers who often can't be as pithy or as accurate no matter how many extra chapters you give them. And this is a perfect example.