It has long been up to the merchant to display different prices for credit cards and non credit card payments. No one is stopping them.

Although at lot of places ban the display of higher prices for credit use. Which discourages most customers, so they settle for showing a single price and skipping the discussion of a discount. Because why would you offer people a way to pay less?

I do not know of any place like that in the US, and would run afoul of this SC ruling I think:

https://en.wikipedia.org/wiki/Expressions_Hair_Design_v._Sch...