these spats are so ingrained that people respond by rote. I want to get out of that and rather than try and "win" an argument I checked out my own opinion. And. I came across this paper. The literature review gave pespective on rail opponents, it was based on work covering a few projects in the NE. So I get that opponents aren't simply ideologues (although the core is). Second, Increased costs are directly related to increased density along a rail line, and this is based on all projects. Ridership is based on population and or job density in the area around the stations (50/acre). So costs and ridership are related. Increased density along route not theft is the reason for overrun.  See fig 3. Steep drop in costs per at 50. I feel better now.
http://uctc.berkeley.edu/research/papers/UCTC-FR-2010-32.pdf