While it does not surprise me that compensation is higher for NYC transit workers wrt national average, it is still striking that the difference is so large. I imagine the avg income in NYC is not >55% more than the national average.
Basically these guys aren't getting their future screwed so they're an outlier. Same problem the Post Office has. When you aren't allowed to skimp on the perks and pass the buck to the government of the future you don't look very competitive.