Brad Biggs at the Chicago Tribune explains why the Bears still have training camp in southern Illinois:
“While only half of the teams in the league go away for training camp, the Bears remain committed to the experience for a number of reasons, one of which is allowing fans a closer look at the team. It also gives the Bears a chance to sell merchandise as fans must enter and exit the ONU fields through a pro shop.”
I’m pretty sure they could find a way to allow fans access at Lake Forest and I know they could set up a pro shop. The guess here is that this has more to do with a promise to the state legislature to have training camp somewhere in Illinois (presumably not in Chicago) in exchange for stadium funding. And they’re a traditional franchise that probably doesn’t like to change the experience.