I have traveled a lot from Chicago to Iowa City, which has no rail service, via both Megabus and a Greyhound subsidiary. Don't know that I would call it a rural route. Or rather, I don't think it's so rural as to be invisible.

People under various hardships have different needs. Greyhound you can pay cash, if you don't have a credit/debit card, though you do need a photo ID. Amtrak is the same, but doesn't go everywhere. Megabus you can ride without a photo ID, but you need a credit/debit card and access to the internet.

When I was traveling that way there were a lot of families moving out of Chicago by bus, with all their possessions in black garbage bags.

Also, prisoners in Illinois tend to get a bus ticket when they're released: http://www.chicagotribune.com/news/ct-prison-releases-bus-me...