The FAA requires a passenger/cabin crew 50:1, which means one steward(ess) for each 50 passengers. But I have seen in many cases that in a flight with 300pax there are at least 10 stewardesses. I am not talking about ultra long haul flights which require a duplicate crew (where the inactive are not on duty in the rest area), but about the medium / long hauls with a single crew on duty.
Why do airlines employ so many flight attendants ? Because of that passengers (yes even in Y) expect they are in a restaurant ?