Eric Schwitzgebel ponders studies suggesting that professional ethicists behave about as morally as people who aren't paid to think about morality:
[W]e might consider some countervailing forces. One possibility is that there's some kind of "moral licensing" effect. Suppose, for example, that a consequentialist donates a wad to charity. Maybe then she feels free to behave worse in other ways than she otherwise would have. Suppose a Kantian remains rigorously honest at some substantial cost to his welfare. Maybe then he feels freer to be a jerk to his students. One depressing thought is that all this cancels out: Our efforts to live by our ethical principles exert sufficient psychic costs that we compensate by acting worse in other ways, only moving around the lump under the rug.