I think the smell is due to the sardine sandwiches. They're actually quite good, and I admire them for being daring enough to offer them, but they do make the place smell awfully questionable. Even bringing home and unwrapping a non-sardine sandwich unleashes the smell. If they get a new place after the current building is torn down, I recommend they drop the sardines and any other fishy sandwich ingredients.
Smells so awful! And maybe #2 is right because they don't actually grill anything in the store. My chicken bahn mi was microwaved if you can believe that action.