The bad, the worse and the ugly!

We already knew that there have been studies showing that ugly people are more likely to be the victim of bias attitudes, including conviction by a jury rather than beautiful people, but this new study goes even further: ugly people are now said to be also more likely to become criminals.
The explanation according to this study may be that because unattractive men and women are less likely to be hired, and since they earn less money, than the better-looking, such inferior circumstances may steer some to crime

"We find that unattractive individuals commit more crime in comparison to average-looking ones, and very attractive individuals commit less crime in comparison to those who are average-looking," claim Naci Mocan of the University of Colorado and Erdal Tekin of Georgia State University.

I find that a bit... far-fetched. I imagine it is hard to say since most of us are... more or less average looking. How ugly to you have to be... to be ugly? How about ugly people why are nevertheless charming? What about those cold beautiful ones? Seems a whole of subjectivity there. But my number one reason for being suspicious of those results is that the research was done by two economists...
Explain that one to me!