You should fight the charges. You are in a gray area as to the sale of the cups rather than the beer, but a good fight could result I the prosecutors choosing not to pursue it or offering a good deal.
Use the Find a Lawyer tool to find a good criminal defense attorney in your area. My colleague provided an excellent response and would be worth contacting. Good luck
The information provided in this answer does not create an attorney-client relationship and is not considered to be legal advice.