It says it right on their website: "Debit cards are not accepted at time of rental at Avis Midtown Manhattan E 43rd St. A debit card can be used to pay for the rental at the time of car return," so with all due respect, it is your own fault and Avis was following all T&Cs fully.

Source: http://locations.avis.com/ny/new-york/e43.html