I was glad to pay around $30 to get from NJ to NY City but surprised to pay almost $37 for us to get to Montauk on the Long Island Railroad. Similarly, I was happy to pay only $64 for us to get all the way from Bridgeport to Trenton, NJ in the wi-fi and comfort of an Amtrak train, but shocked that a taxi wanted $148 for a trip halfway across the island. We traveled 15 miles across the width of Long Island on a public bus for only $3.00 in change, but paid $36 for 18 miles to Bridgport on water.
Some of this surprised me and some of it didn't. Obviously, it will cost more to travel on water than land, but what I learned from tracking miles and cost is that ticket price biases your assessment of value.
I paid a lot more for a LIRR ticket, but the island is a lot longer than I thought (118 miles). Driving appears extremely cheap, but if you add parking it came out to $1.03 a mile which was more than any other mode of transportation on the trip and that isn't factoring in any costs for insurance, repairs, or the car.
At one point in the trip we were stranded in East Hampton for four hours when the LIRR exchanged trains for bus service between two stations and the bus driver missed the transfer. I looked into taxis in place of the $34 we were paying and were quoted $148. It would have been cheaper to rent car or u-haul for the day (I know because I looked), but both were still over $100.
Total transportation cost? $97 each.
(unless you include parking for leaving our car in NJ, then it was about $116 each)
Here is a general breakdown. I used the closest road miles and estimated cost so it's ballpark, not scientific.
Per mile:
Driving = $0.06 ($1.03 with parking)
NJT = $0.25
LIRR = $0.16
MTA Bus = $0.10
Ferry = $1.00
Amtrak = $0.26
