As a small business owner in a past life, it’s probably because you don’t need to; not many businesses have customers looking to shave pennies off the price. The margins and competition in gas stations don’t happen elsewhere, I think.

And you don’t want to. Adding another set of prices and complication isn’t worth it to the business owner.

My 2c

It is my understand that Visa/MC won't be happy if you offer discounts for Cash (meaning they won't let you process any Visa/MC card).

The posted price has to be the CC price, but retailers can offer a cash discount. They don't want to see a CC surcharge.

https://www.cardfellow.com/blog/cash-discount-eliminate-proc...

Nah, they've been fine with cash discounts for a long time. They only became okay with surcharging / adding a fee for cards as a result of a lawsuit in 2013. They'd still prefer businesses offer a cash discount, though. They know customers generally don't take them up on it, but also don't feel punished like they do with a surcharge.