1. Remember the cashier is a human being and the he/she is not being paid nearly enough to deal with your mood swings.
2. If you are expecting to buy alcohol or tobacco, do not bring a minor in with you or someone that doesn't have an ID.
3. Know the law. Remember that when a cashier doesn't accept you expired ID, or your ID that still says "Under 21" even though you are 21, it's not for kicks. Cashiers can be arrested and lose their jobs. It is your responsibility to have proper identification.
4. If you are nice to a cashier, chances are, if there is a problem they will do their best to help you. If you are a douche, they will probably tell you the automated apology followed by the dreaded "there's nothing I can do".
More to come!
