Most people work 8 hrs/day, not 12. If you go to your local supermarket, you'll see tons of people shopping for fresh produce and meat, not frozen or flavorless or expired (???).
You're inventing a total straw man. Yes some people work 12 hour days and eat frozen food but it's a small minority.
If spending lots of time at markets is what you enjoy, that do that. That's what farmer's markets in the US are for. But lots of people prefer to spend their free time doing other things they enjoy. Farmer's markets can get old very quickly too. Sometimes people want to spend just 5 minutes grabbing some ingredients and checking out to make a quick dinner, not 30 minutes visiting different stalls, waiting for the three people ahead of you at each one, and then haggling over prices.