In the back country bear lockers or "hangs" are in every site, However I've never seen a drive in site with any food storage facilities. As a result you generally have little choice but to leave it in the car (NEVER put it in a cooler or similar outside, that's just asking for trouble!). I'd probably recommend the frunk just in case. Additionally there's value to limiting the odours emitted, ziplock bags and such aren't as well sealed as you'd think, and an animal can still smell your food for a ways off, but it will be better than leaving it in more open containers where the smell could travel for miles.
And a good point about toothpaste too. the same rules apply for everything with any odour, so that includes all toothpaste, deodorant, soap, sun screen, bug spray, etc as well as food.