Actually many don't have to since a lot of places don't have recip agreements with GJ and technically don't have to give them a ride. As far as majors I've heard plenty of stories. UA is hit or miss since it's ALPA central, SWA you have to check in with the CA. From who I've talked to, most of them live in ORD or STL and most who commute do it on GJ flights. It's sad...