In the mid-late 70s labels on foods and cleaning products told you exactly what was in them. I remember because my father was an organic chemist by training, and he would look at most labels and explain what was in them, and why we weren't buying them. (My family ended up shopping for most of our groceries at organic food stores.)
It turns out that a lot of people didn't want those ingredients either, and it was impacting sales, so companies successfully lobbied to get the disclosure requirements watered down. These days labels in the US basically tell you nothing.
I studied organic chemistry in college, and there's little as disturbing to me as "natural flavors" or "natural colorings". You have no idea what the chemicals are, what they were extracted from, how they were extracted, and what compounds/processes were used in the extraction. It's a non-label that tells you nothing about what's actually in the food.
We should be entitled by law to know what we're consuming, so that we can actually make informed decisions, and industrial food manufacturers don't want us to know, and have spent vast sums of money to ensure that we can't easily find out.