What if I don't have a smartphone or don't or can't install the app to make direct payment? I personally would not use online payment if I am in store. Privacy

What if I don't have a smartphone or don't or can't install the app to make direct payment? I personally would not use online payment if I am in store. Privacy concerns aside,inserting a card is easier for me compared to unlocking my phone,opening an app and doing whatever is needed to confirm the price abd approve payment. That said,I am sure there are a lot of people that wouldn't mind who have "nothing to hide" and find physical cards inconvenient. This is already being done in east Asian countries. You will still need a card reader in the US unless you wanna go all dystopian like China by forcing everyone to use an app which will be tied to your phone number and other accounts. I would however challenge you to do this in a privacy conserving way, if you can get around anti-money laundering laws. The last thing I need is yet another app and company tracking my purchase history and promising they don't share it with a third party while sharing processed versions of it. Ymmv.