I get it, I do. I've been a migrant in a place with a language barrier on top of sharing that general feeling, so... yeah, sure. In principle.
But the times I've used it it's twice the anxiety, in that I keep fearing I'll mess up and need help, which is orders of magnitude worse than having to go through the register. Just the potential of issues is enough to deter me, but the times I've had the scales mess up or the payment method not go through were excruciating.
There's a bit of a hump you get over, though. I've been recently doing some long franchise-wide marathons and once I got into the groove it was surprisingly nostalgic. It recaptured that feeling of coming back from school and just playing games until I got called for dinner.
I do understand that when I lose that flow I REALLY lose that flow. Not sure if it's age or distractions or what. All I'm saying is you can get it back and it does feel good when you manage it.