Chipotle and the customization habit
Chipotle taught a generation of US diners to expect a bowl or burrito built to their specification, with every ingredient chosen at the counter or in the app. That customization model set an expectation that carries over: people now assume they can adjust a fast-casual order without much friction.
For a burger chain, the lesson is about how customization is presented. Chipotle's strength is that the build is the product, not an add-on. Chains that bury customization in nested menus lose people who are used to one-step ordering.