My department was outsourced this year. So, I have been working as one of those weirdos while I seek new employment. Most businesses seal the food so the driver can’t touch it without it being VERY obvious. (Like a ripped sticker seal) Just know that not everyone delivering is some creep who wants to put poop in your food. I personally don’t even put orders into the cabin of my car. It goes into the trunk inside a sealable cooler that I provide/clean between shifts.
That’s why I call my car my home studio.