We generally eat at 515-530 during the week. If my son has early hockey then we eat earlier. On weekends we eat later. During the week I like to have my kids in bed between 8 and 830..... My 8 yr old however for some reason does not need a lot of sleep and he is still awake reading at 10:30....he gets up on his own at 7:30. My in laws all eat at 4 o'clock and its seriously annoying. My sister in law puts her 11 yr old kid to bed at 7.... Needless to say its a big bone of contention for holiday dinners cause they all want to eat early and my youngest naps till 4.
As far as I'm concerned most working people don't get home from work till at least 4:30-5 so unless you had your crock pot on all day there is no way your eating till 530 and that's if it's leftovers or something quick. No I don't believe for working families that eating at 4 is normal