They aren't typically found in nature in the form in which we consume them. They require human processing (even if it's much less processing than what goes into making a frozen pizza).
Salt is. In my grandma's village we have both natural salt rocks and also salt springs people use for cooking, conserving white cheese or preparing pickles. And that village is not an exception in my country, it is the rule in all mountain areas.
i'm curious specifically about what you think we do to salt that changes it so dramatically