Adding gratuity doesn’t always make sense, but the obligation to has been entrenched as a societal norm

You arrive at a pizza place to pick up your order. The credit-card screen asks if you would like to tip and gives some choices. It seems strange to tip the cashier, who did nothing but hand over the pizza. But it also seems a little harsh to select “no tip” instead of one of those more generous options.

What’s the right thing to do?