They said that DTF wants to come to San Francisco, but local food safety laws make it impossible. Specifically, the metal tins they serve the dumplings in are for some reason a no-no according to SF rules. I have no idea why, and they didn't either. They just knew that was the main impediment to DTF gracing SF with delicious soup dumplings.
--Brendan Mulligan, Quora, on another example of San Franciscan over-regulation. HT: JC