To be fair... money has different value to different people. I doubt any billionaires would care to waste 10 minutes of other people's time to save much money, because money doesn't have that much value to them. On the other hand, college students that eat lots of ramen are already valuing money more than their own health, so it seems natural that they'd place far more value on the money, even if they place the same value on other people's time.