I think it's implied that there's a difference between a taco stand that is just running in a local geography and not really innovating, and a company like Chip

I think it's implied that there's a difference between a taco stand that is just running in a local geography and not really innovating, and a company like Chipotle which spent a lot of time and effort optimizing their business model to make it replicable while taking large investments to pursue fast growth. He's not referring to Chipotle in the essay. It's why says "restaurants" and not restaurant chains.