This is one of the several places that pop up at street fairs that say they are offering free evlauations for your back. My BF did this a couple years ago because he was involved in a car accident.
The free evaluation involves him feeling your back maybe giving you a slight adjustment and then tells you that he could help you more if you got some x-rays (not free) and see him a few more times for regular adjustments (also not free).
more