Thats why we must never forget about the importance of small transactions like those. Buying some coffee in exchange of Bitcoin impressed them more than any of the revolutionary protocol tech stuff you could explain them.
Careful, you might prompt some nutjobs to lecture us all on the evils of permanently storing cups of coffee in the holy ledger.
They'd have you believe adoption in this manner is irrelevant because Bitcoin is just going to be a settlement network for the wealthy. They'll tell you Bitcoin can't scale to allow everyone to transact in such a fashion, so there's no point in trying and we should concede defeat now. They honestly believe it doesn't matter if the developing world, or even the average user, is priced off-chain, because the only important aspect of Bitcoin is how cheaply you can run a full node.
Personally, I think great things will happen if more people use Bitcoin for everyday purchases without relying on banksters or card providers. I agree that small transactions like that will be vital for future success.