> You swipe a card in a reader instead of having to count out cash. That's the major benefit.
It's not just the counting out part that's inconvenient, and it's not just cash. There's also receiving some arbitrary amount of cash and coins that you then have to dump into your pocket/wallet/purse and deal with until your next shopping trip. Coins dangling in your pocket and having to fish them out every time while making sure you don't lose them beforehand is not exactly fun.
It's not just the counting out part that's inconvenient, and it's not just cash. There's also receiving some arbitrary amount of cash and coins that you then have to dump into your pocket/wallet/purse and deal with until your next shopping trip. Coins dangling in your pocket and having to fish them out every time while making sure you don't lose them beforehand is not exactly fun.