Booting Scam

This was today. I was taking my friend to a bus station in metro Atlanta. I parked in a parking lot next to the bus station. After heading to the bus station to check the times, I immediately came back to the parking meter in the parking lot to pay for my ticket. At that time, it had been approximately 4-5 minutes since I left my car. As I was paying for my ticket, a ABS (Advanced Booting Services) representative came up and told me that I already been booted; I was also fined 75$. I was confused and he told me to meet me at my car. I inquired for the company's telephone number but he told me that they were closed on Sundays. I asked him for his supervisor's phone number but he told that "he wasn't about to call his boss on a Sunday". I also asked if I could wait till tomorrow to call the office but his response was "It'll be 150$ tomorrow plus you'll get towed”. I told him to give me about 10~min to figure things out. He agreed. I tried calling a few people including the closed ABS office. I got extremely frustrated and just paid the 75$ and left. Additionally, some other people near me got booted as well for nearly the same reason. I completely agree that I should have paid first before stepping inside the bus station but I don't agree with the part that the I was not allowed to call his supervisor. I was debating on whether or not to call the police at that point but I figured it would have been pointless. Any suggestions on what I should do from here on out? I was planning to call the office tomorrow but I don't think that would be much help.

Thanks in advance!