ezStorage review: Charged for an entire month although storage unit is vacated

I had been renting an EZ Storage unit in Woodbridge VA, since Oct 2014 when I deployed to Afghanistan, I always paid on time using a credit card on auto payment. Today (August 1st 2015), I vacated the unit before 5pm and upon check out was told that I would be charged the entire $157 for the month of August anyway. I normally would not complain however, I was shocked at the Store Manager's lack of customer service, telling me "it was in your fine print and you needed to be out yesterday before 5pm". I was shocked and appalled that a Manager would treat a good paying customer this way, especially one that served overseas to protect our freedoms at home. I just want to be refunded or prorated for the 1 day in August, something that any reasonable business would normally do. If EZ Storage plans to adhere to this policy and not provide good customer service, I will spread the word to all my military colleagues to never do business with this company ever again.