The MTA spends over $10 billion per year on labor, much of it redundant (e.g. two drivers per car): http://interactive.nydailynews.com/project/mta-spending.

People say "oh, but diverting tax dollars from MTA, etc." The NYT pegs that at about $1.5 billion over two decades (since Pataki). https://www.nytimes.com/2017/11/18/nyregion/new-york-subway-.... That's $75 million per year, a drop in the bucket in comparison. About enough to build a mile of subway line.