Things that are "natural"

All over the place, I see the phrase "all natural" or "only includes natural ingredients".  Now, I love Whole Foods as much as the next person, but I really have to wonder why everyone is so obsessed with things being "natural".  Let's list some natural things:

- Poison arrow frogs

- Necrotizing fasciitus (don't click if you've eaten recently)

- Anthrax 

- Arsenic 

Hell, that last one is on the periodic table of elements.  It's one of the fundamental building blocks of the universe.  Can't get much more natural than that.  And it'll kill you real quickly, too.

Now, for some unnatural things:

- Many antibiotics

- Many vaccines

- Many drugs (most drugs probably by now)

- Air conditioning

- Computers / the internet

So, remind me again why anything "natural" in inherently better than things that aren't natural?  If a cereal box wants to explain to me why I would care, what chemicals are removed, and what risks would come from using food treated with those chemicals, then maybe I'd listen.  But generally we get the "all natural" plug and that's it.  I'm interested in reading up on potential harmful effects of not using natural or organic products, but generally we're just bombarded by pictures of plants and trees and told that it's all really good for us.  

EDIT: One quick example.  I decided to google "dangers of preservatives" and this was the first result.  It's a huge long article listing all the horrible things that are in our food.  However, it fails in almost every single case to give any evidence whatsoever of harm done to humans, especially in the amounts consumed.  Our body is great at filtering things, and if trace amounts of some poison make it in, we'll filter it out.  I'm not saying that I want my food to be filled with the stuff, but I'd like to see something a bit more concrete before spending 50% more for food that won't last more than a couple days in my pantry.