Funny thing - the young cashier really took it in his stride. This suggested to me that he recognized the folly of the old guy - and might have been clued-in to Bitcoin. He didn't seem at all confused.

I doubt the senior will be around to see adoption in his lifetime - I'm fairly old (a Gen Xer) but he was a really, really old...

But, stranger things can happen. I'd love if our paths did cross again - with me paying via Lightning and him with his jaw dropping as I go on my way...