Yeah. I guess people would have a hard time paying the actual cost but that's more of a perception problem. The system would have to be cheaper than owning your own car. People are paying the cost now it's just hidden in their existing budgets.
As a little exercise, I tried to figure out about what my current per-trip cost is for my 2001 Tundra pickup. It cost 18,000 so lets assume I can drive it for ten years so the yearly cost is about $1,800. During that time, I'll figure that regular maintenance will average $500 per year. I drive around 16,224 miles a year making six 52 mile round trips a week. I get about 18 miles per gallon so my yearly gas bill should be around $2000. I also pay about $1,200 in insurance. That comes out to a total of $5,500. I'm figuring on 312 commutes to work a year so every single time I drive to work and back it costs me about $17.62. I probably wouldn't pay $3 for a one way bus ride but I'll pay much more than that to drive without even knowing I'm doing it.
That's part of the political problem. You can create a system that's much more efficient because you increase the ride density. Put an average of four people in that car without adding too many miles to the trip and you greatly decrease the per-person cost. There are billions of dollars in potential savings! Plus, if you can get enough people using it, it decreases traffic which increases both fuel and time efficiency. In many places, it would speed up commute times because even though you're making more stops, you wouldn't be stuck in traffic.
Bootstrapping the system would be the hard part. If you can't get enough people to use it, it wouldn't work. The wait times would be too long. I have my doubts about whether you could ever get it up and running but if you could, it would be the only mass transit system that would work out here in the west.