The problem historically was that when consumers were given detailed ingredient labels, they often decided to not purchase the products. Chemical and food manufacturers spent vast amounts of money to get ingredient labels watered down so that consumers wouldn't see the chemical names. In the 70s labels were much more detailed.

Labels like "natural flavors" exist to cover up what's actually in the food. "natural vanilla flavoring" sounds much nicer than "vanillin and acetovanillone extracted from waste sawdust".