What people say they want and what people choose to buy are very different things.
If you ask people "Do you want ____" in isolation, they'll always say "No" if they thing you're asking about has any negative connotation.
If you put two different products on the shelf next to each other that differ by that same thing and even advertise it prominently (e.g. one says "No artifical dyes or coloring") most people would probably choose the brighter one because, at time of purchase, their reveleaed preferences are actually different. Now add an extra $0.10 to the retail price for sourcing more expensive natural colorings and even more people will choose the artificial coloring version.
This pattern plays out prominently in all things food related. If you ask people "Do you wish the food supply was healthier?" everyone is going to tell you "Yes". Then when they're deciding where to go for lunch or what to order, they'll skip right past the healthy items and choose what tastes the best.
These hypothetical free-lunch questions are useless because consumers will always claim they don't want the thing they don't understand. If you ask people if they want their food to be "preservative free" they'll tell you yes, until they see their food going bad immediately and their options dry up. Ask if they want "anti caking agents" removed from food and they'll emphatically agree, until their shredded cheese is sticking together. Food science and popular opinion are two different worlds.