I am surprised it is $2.50/rental day, even if you only use it on one day.
Hertz charges on day of use only.
Terms are found here
http://www.avis.com/car-rental/conte...d=T4M08S02#top
Its too bad that EZ-pass takes 24 hours to activate/change the car/license. I still have one from when I had a car in New York and tried to use it for a weekend rental but the EZ-pass agent told me it would not work for the first day.