Palmer, Reifler & ociates Civil Claim... should I pay?

Ok here's the deal. About 3 weeks ago I was at a mall in New York and I got my socks soaking wet so I decided to go into sears and take a pair out of a baggie. I thought it was no big deal at the time. Stupid, I know. Halfway down the road the security comes and gets me and bring me into their office and tells me I am not going to be arrested but I am going to get a letter demanding I pay. the total coast of the socks was $11.50 (although I only took one pair, again stupid, I know). I received the letter that demanded I pay $75.00 to their office. it says if I pay that I will be cleared. I have read into Palmer, Reifler and found that most of the time they claim to have not received the money and I was wondering if this is likely to happen to me? and what happens if I don't pay? Thanks for the help.