It seems there's an association between spending money on one's self and selfish conduct, and it doesn't require actual spending. In this 2009 paper Roy Y.J. Chua and Xi Zou, both professors of management, found that just getting people to think about that kind of spending was sufficient to make their decisions more selfish.
The pair showed 87 university students pictures of shoes and watches and had them complete a survey about the products. Then they answered questions about how they would behave as a chief executive in each of three hypothetical business decisions. Half the group had seen pictures of simple, functional shoes and watches. The others had viewed, and then described, top-end luxury goods.
Those who saw the luxury versions were significantly more likely to choose the selfish path in the business decisions. They were more inclined to OK the production of a car that would pollute the environment, the release of bug-riddled software, and the marketing of a videogame that would prompt kids to bash each other. That suggests, write Chua and Zou, that "mere exposure to luxury caused people to think more about themselves than others."