It ultimately comes down to money. Radio is a business, and essentially there are 4 major players who own all of the radio stations in the Detroit Market.
Greater Media owns WRIF 101.1, WMGC 105.1, and WCSX 94.7. The market dynamics for radio, like newspaper, and television have changed rapidly over the past decade with the rise in other forms of media and electronic devices. They have had to adapt in this new era of podcasts, iTunes, satelitte radio, and smartphones.

97.1 has produced solid rating, much in part to the fact they have play-by-play for the 4 major sports teams in town. Greater Media likely though they had a better chance of making more money by flipping 105.1 from adult contemporary [[aka soccer mom & dentist office music) to sports talk [[aka guy talk). The 105.1 flip will be judged by Greater Media as to whether they can operate it profitably. As long as revenue can justify the costs they will be ok. Right now they are starting out rather cheap, with most of the day being ESPN radio national content.

Radio is one of those things that we few sort of like a utility, but ultimately it is a for-profit business.