Forbes is a retarded "finance for pop-culture" type magazine. They publish 100s of such lists a year; most of these make no sense whatsoever. I think they just pull out many of the evaluation numbers out of their ***.
According to this list TX, Mich St. and Arky should have three of the wealthier ath dept's with both a top 20 football and basketball program. We're #2 in Fball on their list.