Last week i was standing in line at the coffee shop, waiting for the woman in front of me to pay. She signed her credit card slip, slid it across the counter to the cashier, and turned to walk away. The surly young cashier called after her: “Thanks for taking care of us.”

Astonished, the woman turned back to the cashier. “What do you mean? I always take care of you guys.”

The cashier became defensive. “I didn’t mean it that way. I always say that to everybody.” She glanced at me and added, “I’ve said the same thing to her twice today, haven’t I?”

This young woman has never even bothered to smile at me and almost always makes me feel that I am imposing on her time. I would have remained silent, except for the fact that she pressed the point. Looking directly at me, she demanded, “Don’t I say that to you all the time?”

I was forced to reply that she had never said that to me. By this time, the whole incident had become uncomfortable for everyone concerned.

The issue at hand was the woman’s failure to drop some money in the tip jar sitting on the counter. Tip jars have begun appearing in the most ridiculous places. First it was at the cash registers of buffet restaurants. Then it was fast food places. And now they occupy counter space in most coffee shops as well.

I understand that tipping is expected in this country, but until recently I thought the point of tipping was to reward a waitperson for service provided. Now it seems we are expected to reward people for just being there and doing their job. Frankly, I’ve always wondered why I am expected to leave a tip in a buffet restaurant. I get my own food, stand in line to pay, pour my own drinks, and seat myself. Ditto for fast food places. And coffee shops aren’t much different, in my view.

The bottom line here is that tipping is a privilege, not a right. I’m a fairly generous tipper; I am always willing to leave 20 percent. But if you do nothing to earn it, you do not get it. And until this young woman learns the meaning of service with a smile, she gets bupkus from me.

Yesterday I was back in that same coffee shop and noticed a change. The tip jar now carries a sign: “God Knows When You Don’t Tip” I suspect God would remind her that He helps those who help themselves.