"Omakase"? (Sorry, old habits die hard.)

The traditional response is to ignore the matter, for the comfort of everyone else. I would THINK of dropping a note off to the offender telling him he was ruining everyone else's meal. But I wouldn't do it. It is not that I would care about his feelings, since he probably doesn't have any , but in the long run, silence is best. Avoids the aginbite of inwit, y'know.