No one likes paying tolls, but avoiding them also has a cost.
Getting off I-80 at Gary and taking that route to avoid tolls adds about 30 miles, but with the lower speed limits and stoplights, it's also going to add at least an hour to your drive.
To me, that's not worth it to save $25 in tolls ($20 with an EZPass).
I'd just take I-80 from Utah all the way to NYC.