Even the company truckers need to be paid a premium to go into NYC (delays, congestion, tolls, danger, etc) and those premiums will only go up. At some point, people will say "screw it, simply isn't worth the trouble" and the rates will start to go higher. At some point, regularly supplying the largest cities becomes untenable just as it did to Rome around 470 a.d.
A friend’s brother took a job in Chicago. The Weekend before starting he drove into town. At the first stoplight a car full of black men pulled up beside him and they pointed guns at him. He turned around and went home. Monday, he called in and quit.