They only accept cash for liquor sales. It's 2013, who carries cash?? Ridiculous. I realize that they might be trying to circumvent the credit card charges, but the prices were not discounted enough to justify a marginalization like that. They try to point you to the ATM (which they probably own) by the front door. Underhanded business practice.
Update 3/8/2014: I received a thorough email from the owner, explaining the ins and outs of why they do not accept credit cards (still no idea why they wouldn't accept debit) and have decided to up my review to three stars. In light of the fact that the employees I dealt with were rather nonchalant about the fact that they would not accept our cards, and provided no explanation as to why, or any apology for the perceptible inconvenience, I don't think I can go higher than three.