Tip the Cashier?

This morning, upon purchasing my staples for the office (i.e., coffee, diet soda, and gum), I received 5 cents in change from the cashier. I put the coin into the large paper cup saying "tips", in black marker, I think. I felt a little guilty, maybe even embarrassed, about putting in such a measly amount of money, but then I thought to myself, why tip a cashier anyway? When did that start? It's not like they're doing anything special for me to be deserving of a gratuity, like a waitress who takes 5 hours to give me the wrong order, or a cabbie who thoughtfully takes me on a narrow path between a truck and bus and brings carsickness to new heights. These people are just taking my money!

I must admit though, the cashiers at this store are really quick and efficient, to the point that they make me so anxious that they end up waiting impatiently while I nervously fumble for my change. If only these cashiers could start working at Rite Aid- the world would then be a better place.