You probably get it by now, but we're going to keep rubbing your face in the facts, nonbeliever. A bit of body odor might seem like a minor inconvenience, but it gets a whole lot more important when sneaking up on an animal that hasn't spent the last millennia losing its survival instincts means the difference between feasting and starving. Finally, an accidental fire near your ammo stores that could easily have been extinguished with a dose of nonflammable powder will certainly put a damper on your plan to make it through the end times in one piece.
In tropical areas, a survival kit may have mosquito head netting, additional insect repellent, anti-fungal cream, a machete, water purification tablets, foot powder, matches, a flint strike, a compass, a wire saw, a space blanket, medical equipment (gauze pads, elastic gauze bandage, antiseptic creams, anti-malaria tablets, anti-infection tablets, bandages, etc.), salt tablets, a fishing kit, snare wire, extra socks, a candle, a signal mirror, flares, a sewing kit, safety pins, tinder, tape, a whistle, and rations.
Your run-of-the-mill shoe stank might not pose much of a survival threat, but trench foot certainly will; baking soda is great at absorbing the moisture that might otherwise literally cause your feet to rot off your legs. As for the health of your teeth -- it will be pretty hard to get through your day's rations of homemade jerky and hardtack without some high-quality chompers. And you certainly don't want to rely on that pesky fluoride that will "kill your brain over time" (um, what?).
Earthquakes, tornadoes, and hurricanes can cause you to leave your home or even be trapped there. Roads could be blocked due to fallen trees, power lines, or even damaged earth from the natural disaster. Rescue crews can not be in all places at once. You may have to wait it out for quite a while before its over. You won't be able to go to the store or to the corner market.