Court documents and surveillance video shows 22-year-old Tamika Garris rang up Gray's purchases and then picked up his wallet after he left it on the counter. Several hours later, she went to another register and used Gray's credit card to buy cigarettes for $13.
Later, Garris is accused of going to a liquor store and forging the mayor-elect's signature for $25 in liquor.
Garris was arrested Wednesday and charged with credit card fraud.
A message left for Garris' attorney was not immediately returned Thursday.