Fox falls into a category of people that the University of Michigan marketing professor Scott Rick has spent years studying: “tightwads,” or people who have trouble spending their money.

Differences between tightwads and spendthrifts are greatest in situations that amplify the pain of paying. But it may be that spending money on gifts is just as painful as usual for tightwads.

Everybody knows them - those expense account tight-wads who go out of their way to keep business-travel costs low for the better of the company. But do the bosses notice? Photo: Getty Images.