When you are standing in a line of people, and they're all waiting on you, there's a bit of pressure (real or imagined) to not be the one wasting everyone else's time.

Given the option between tapping a card, which Just Works, and fussing with Apple Pay that (in their experience) doesn't, the obvious choice is to not bother with using apple pay.

That's not to say that your perspective isn't informative, but rather that the original complaint likely comes from a place of social stress rather than fractional seconds being the issue.