Food supplies in a bug-out vehicle include hundreds of pounds of wheat, rice, and beans, and enough honey, powdered milk, canned goods, bottled fruit, vitamins, dehydrated fruits and vegetables, salt, pepper, spices, and oil for several months. In addition, the kits often contain high-calorie energy bars, a cooking kit, utensils, liquid soap, and towels. The water supplies may include bottled water, filtering kit, bottles, collapsible water containers, and chlorine bleach for water purification. Food preparation and washing equipment may include items such as a grain grinder, a bread mixer, a strainer, a manual can opener, a steam canner with canning jars and O-rings, cutlery, knives, an electric 12-volt cooler icebox, kerosene lamps and heaters, kerosene or propane stoves, extra fuel, a clothes wringer, a foot-operated treadle sewing machine, and an electric hot plate (which would require an inverter to operate off a car battery).
Astronauts are provided with survival kits due to the difficulty of predicting where a spacecraft will land on its return to earth, especially in the case of an equipment failure. In early US space flights, the kit was optimised for survival at sea; the one provided for John Glenn on the first American space flight in Friendship 7 contained "a life raft, pocket knife, signaling mirror, shark repellent, seawater desalting tablets, sunscreen, soap, first aid kit, and other items". A survival kit was provided for the Apollo program which was "...designed to provide a 48-hour postlanding (water or land) survival capability for three crewmen between 40 degrees North and South latitudes". It contained "a survival radio, a survival light assembly, desalter kits, a machete, sunglasses, water cans, sun lotion, a blanket, a pocket knife, netting and foam pads".
It turns out that when you're down to your last moldy hunk of bread and giardia-laced mud puddle, letting it all melt away in a cloud of smoke for a few precious moments can mean the difference between giving up and giving the rat (eating) race another go. If history has anything to say, it's more common than you think for people to happily give up MREs and gunlord harems in return for hastening their ends with carcinogens wrapped up in tidy paper packages. In traumatic situations like war, cancer sticks are often valued more highly than food. Even in the current (more or less) pre-apocalyptic global economy, cigarettes are one of the stable forms of currency.
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!