> But, surprise, this second option doesn't scale. Because as soon as the nice asian shop goes viral, they realise they can’t keep up with the demand at all. And so they will probably refuse lots of customers. (Note, I’m not even considering the option they might increase prices)

I've always wondered -- who cares if you hit a scaling limit? Why can't you just coast on huge demand, refuse some customers, and have a sustainable business that's founded on trust in the quality of your product?