This video was made in October 2017, and the guy was shopping in a Tokyo supermarket, and paying with Bitcoin.
https://www.youtube.com/watch?v=W4J_myvNYG8He seems to have had his transactions confirmed almost immediately, and I don't understand how this happened. I can see it working with the lightening network, but I don't think that was available then. Is it just that the shop is prepared to take a risk, and as long as the transaction was sent, they don't bother to wait for a confirmation? That seems to be a bit risky, as if it was sent as a no/low fee transaction, there must be a risk that it is never confirmed.