>Like large employers can dangle some pretty substantive carrots but I don't think courts would let them get away with any sticks.

The courts already let them get away with it. There's nothing illegal about discriminating against people based on their commutes. The employer can do anything they want, up to and including termination (or refusal to hire someone in the first place).

Commute discrimination already happens, here's one article detailing research on the topic: https://www.bloomberg.com/news/articles/2018-08-30/inner-cit...

Here's another article about it: https://www.boston.com/news/jobs/2018/03/26/no-offer-because...