Pizza chains have delivery fees that aren't paid to delivery drivers. Restaurants have service fees for cooking food and convenience fees for placing orders (even if paying, in cash, when you pick up), on top of the sticker price of the food itself, which used to just be the price.

Some people in this thread have talked about stores having signs saying they'll round change up to the dollar if you pay in cash, and advising to pay by card if you want exact change. I've personally seen businesses have signs on their cash registers that say "our cash register is easily hacked, we strongly recommend paying by cash instead instead of card" (I'm assuming so they can cheat on their taxes).

Businesses will do anything they can get away with to make more money, and they can usually get away with tiny fees like this. It's only a few cents, right? Except for them, it adds up.