Very well said WH - I too would like to think I am a "Mensch" though not necessarily because I don't believe I need money or because money has never brought me happieness.
On the contrary, when I have enough money to pay my bills, eat well AND buy myself a few extra goodies, I am quite happy. When I can barely make the bills, am struggling to invent cheap meals and can't even afford to buy myself a skein of yarn to play with, I am less happy - though not really unhappy. If I can't pay my bills or buy food, then I am unhappy.
However, that said - I would go out and forage in the local forests for food or even approach a Christian church on free meal day - before I would kill someone for money. It's wrong. Kill to defend your life, kill to defend the lives of your loved ones, sometimes even kill for punishment of hideous crimes - but never kill for money, possessions, lands, etc.
If the devil gave me such a box (and considering I don't believe in him that would be a stretch lol) I would buy one of those fireproof safes, lock it inside and lose the key - technically, I'd still have the box, so it wouldn't be lost, technically, if I really wanted to get into that safe I could even though it would take great effort, technically it would be safe from destruction - and from all the various tales I've read about the devil, he's always beaten by technicalities