WKU Rivals site publisher here. I told the UK fans on their board when they brought this up the exact same thing. Which is that Brohm isn't all about the money and if/when he leaves WKU it will be for a destination job. He turned down interviews with Maryland, Virginia, Illinois, and a few others schools recently. He wants to build something at WKU.
One thing Schnellenberger told Jeff when he got the WKU job was not to jump at the first opportunities and that the grass isn't always greener on the other side. He also told Brohm to build something that could be his much like Howard did at UofL. Brohm has seen other coaches jump at the first P5 job to come calling only to be forced out 3-4 years later. He will make about $1.2 million in BG this year. Cost of living is not near as high in Bowling Green as other places around the country. A person can live extremely comfortable here on that type of income. I have heard that Brohm wants the UofL job eventually. He loves the state of Kentucky because its home to him.
Brohm may decide to stay at WKU until Petrino leaves town again. But if he does take another job it will be a team far better and in a better position to succeed then the UK, Purdue, Vandy, or Virginia's of the world.