Don't understand that thinking. Maybe someone can share the rationale. I always thought that my local Walmart (which hasn't been refurbished in years) just was as the bottom of the list for improvements---my 10-min drive radius is chock full of competition from every national and regional chain.
NFC makes life so much easier everywhere else....of course that means carrying only one card or wrapping the others in a sleeve.
Walmart would prefer that their customers use Walmart Pay, via their app.
They're large enough to not care about any potential shopper resistance, and TBF, there are so many ways to make payments now, it's not a practical issue for most people.
However, like Costco, Walmart despises the merchant transaction fees that the credit card associations charge, and if it could get away with not accepting credit cards, it would probably stop. That could discourage a lot of shoppers and any potential sales dent would not be palatable. There was a time when Walmart did not accept AMEX, which has the highest merchant fees. I've run into more than one situation where a vendor has stopped accepting AMEX.
Costco makes its profits on membership fees, and is a place people generally want to shop, as well as having a desirable customer base, so they can choose to limit their card acceptance to the one that gives them the best deal, currently Visa. Along with their soda vendor, which has flipped back to Coca-Cola. Costco also exerts its market power, to do what they think is best for them. It has even banished Apple in the past, which did return, on Costco's terms.
Edit--forgot to add that NFC was part of the package of the big EMV tokenization mandate that forced retailers to upgrade their payment terminals, or bear the liability for fraudulent card activity. So that capability has been in the hardware all along; it was up to the merchant whether to use it. Home Depot and Lowes, which were also among the last of the holdouts, actually accepted NFC early on, albeit unofficially. But they later chose to turn if
off.