> Are you suggesting that after that dialog, were I to put a dollar bill down on the table and wander away with the tchotchke, there would be courts that would hold I didn’t actually buy it?

If the proprietor was aware of it and didn’t object, probably not, because the tender of payment is an offer on the negotiated terms and its acceptance is…acceptance.

I don't know - that seems a little bit wonky to me - you started off with the idea that there was no intent to create legal relations, but somehow that occurs as soon as the dollar bill appears, and then one party accepts by silence?

I would say it's pretty clear that buyer and seller in a yard sale are intending to create legal relations - viz. exchange goods for cash - this isn't one of those weird areas like family agreements or pacts between friends.

If, at the point the buyer put the dollar on the table, the seller suddenly changed their mind and said "no, it's not for sale actually", would a reasonable bystander actually think that the sale had been agreed? I would say yes.

BTW if you think this one is bad, check out the fun and games trying to rationalize offer and acceptance in the Amazon stores without checkouts: https://www.oscola.org/post/amazon-fresh-offer-and-acceptanc...