Don Boudreaux over at Cafe Hayek arrives at the problem with concerns about income inequality:
If a millionaire embarks upon a life of successful house burglarizing, the problem with this activity isn’t that it further increases income inequality; the problem is that the activity itself is immoral and destructive
And so it is with any activity that acts to either increase or decrease inequality; which makes the effect completely irrelevant in a discussion about morality.