The idea of dating women who make more money than men creates a rift in the traditional role of man to woman, as seen through the eyes of man.
Throughout history, man’s role was to be the provider, the breadwinner as it may in the relationship. It was, and still is an important role, for the male’s ego which bruises quite easily. Making money is still of the utmost importance to the male who identify that with success. A female that equals or surpasses a man in terms of salary may very well threaten his ego and manifest itself through anger and frustration (brought on, no doubt, by jealousy).