Sure, saving forty bucks sounds nice until you realize it's just other broke people covering for a city that won't.

Yikes, hauling water beats a nine grand sewer bill any day.

The thing nobody talks about is what you do when the bus schedule doesn't line up with your trip. I looked at the Phoenix to Tucson route once and the last bus back left around 6pm, which kills any evening plans. Rental car you just leave whenever you want. That flex time is the real cost, not the ticket price. If your gig ran late you'd be stuck paying for a hotel night, and there goes the savings.