People today are increasingly demanding restaurant food that is ethical, interesting, and of high quality. Or at least, that’s what they say they want. True demand, in the economic sense (which is the sense that counts in the food industry) is what matters here. In other words, it’s easy to say you want x, y, and z when some reporter or university researcher or PETA rep with a clip-board gets in your face. But when you’re in line at McDonald’s, you may choose differently.
Check out this short piece on that topic:
Millennials are lying about what they want to eat, and it’s destroying fast food
“…All of these efforts flopped, and there’s an important reason: Millennials are lying about their food habits.
Millennials say they want food that is high quality, free of additives, and sustainable, but they aren’t always willing or able to pay for it….”
The Food Ethics Blog 
It seems to me that the problem isn’t the discrepancy between what millennials want and what they buy (we can hardly expect an environmentally conscious individual living on a low income to afford an entirely organic pantry), it’s that the production of unethical, unsustainable, conventional food is so ridiculously cheap. I’d say it’s less the role of the individual (although one should certainly try to be a conscious consumer when possible), and more the role of governments to regulate said production systems to make them bare environmental and social damage costs, which would then be reflected in the price, and hence organic or ethical food would become more competitive. In short, blaming the consumer for unsustainable fast food chain tactics is not focusing on the core of the problem.