I find the Chain vs Local debate unanswerable and pointless.
It is the aggregation of personal choices, and there's no debating taste. For people who like either sort of thing, that's the sort of thing they like. What's right* for Assembly is whatever people like at Assembly and vice versa.
Should there be only one Mike's Pastry, Regina Pizzeria , and Modern Bakery in the North End or can we get clones at Assembly, Quincy Market (and
16 others), and Medford Square, respectively?
*There's no right/wrong. There's no must/should. This can only be a "the market will decide".
When you find a perfect local gem in someone else's town, if enough people wish for a branch of that store "back home" in your town, you'll likely get one. It is from this that the chain imperative arises. Successful one-store retailers get systematized and cloned.
Unless the store's success is intimately tied to the owner/expert/founder (as, say, ballet shoe fitting turns out to be) stores get turned into chains because we love them too much.
That love determines what stores work where. Chains succeed because they have a well-thought out system that delivers people what they want, and people like choice and their tastes differ.
Personally, my favorite North End Pizza is Ernesto's. It is charming as a hole in the wall on Salem St, but if they wanted a branch walking distance to my house, I'd be happy to see it displace my local hole in the wall.