no it really isnt possible. Ive worked at a grocery store for 4 years now, you CANNOT get cash back unless you know the PIN number for the Debit card.
quote since i doubt you read it:
do not offer cashback on payments by credit card because they would pay a percentage
commission of the additional cash amount to their bank or merchant services provider.
your just lucky your not me. i forget what i'm talking about mid sentence..... it's entertaining... - bombin_baker*