I store food in the vehicle, but I don't cook directly out of the back so I'm not too worried about the scents. I keep my key fob nearby when I go to sleep. My theory is that if an animal is curious about the vehicle, a sudden noise/light from it would discourage the animal. Probably less effective on bears that are used to people.
I do hang a bear bag when backpacking.
Hmm, good to know. I think that definitely helps make a difference, but it still makes me wonder since I doubt these storage systems are 100% sealed. Maybe it's just me over thinking it, but just a genuine question.
Very safe to leave the food in vehicle.
Having said that precautions still need to be made. Seal food in the cooler, in bags and dry boxes etc. Don't leave a dirty camp. Don't dump your food leavings around camp and don't dump dish soap, toothpaste etc close to sleeping quarters and they'll leave you alone.
Leave your garbage around camp and yogi will be sniffing around looking for more. He may smell the things in the car and be curious but it's unlikely.
If he starts knocking on the window you should have time to at least shine your flashlight in his eyes before he gets in. :-)
Seal food in the cooler, but are these items/storage systems 100% sealed? I feel like while they do seal a good amount of scent, I'm worried animals can still smell it, since i've heard stories of people leaving unopened food attracting animals. Definitely, I don't dump anything around when I go out. I always have food stored in a bag hung on a tree, same with trash.