Being at the airport three (3) hours before your flight is plenty of time.
I think your parents are making a > good < decision to stay at an airport hotel the night before. Try to get to the hotel during the early afternoon so you can all relax, use the pool, and otherwise make Friday the real beginning of your vacation.
Check the restaurant options for the terminal you will use. If there is not a restaurant that offers a real breakfast then eat at the hotel before taking the shuttle or taxi to the airport.
https://www.flysfo.com/shop-dine-relax/dining