You’re buying and bringing pre-cooked beans that have been dehydrated or just dry beans? Instant rice (which has been cooked and dehydrated) or just regular rice you have to cook for a long time? Dry beans have to be soaked for hours and then cooked for like half an hour unless you have a pressure cooker right?
If you cook everything and dehydrate it you can just add hot water and the food soaks up the hot water and you can eat it, like making instant ramen noodles except whatever meal you want. You can do this with purchased instant rice and instant beans, and then dehydrate the chicken and tomatoes and onions and everything else separate, I just find it’s cheaper for ingredients to buy regular rice and beans and cook everything together and dehydrate it together, plus then the flavors get cooked into the beans and rice much better.
Admittedly, beans and rice is more of a starter entry meal into dehydrating because it’s hard to mess it up. But more complex meals like a dehydrated chili or dehydrated chicken curry, you can’t just “take on every camping trip” especially if you are sleeping far from your vehicle.