system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why doesn't someone start a blood factory? Instead of blood donation, blood jobs!

I was wondering why someone doesn't just go to one of the most populated places on Earth (China) and start a sustainable way of life that revolves around the production of quality blood.

Just build a mini village, grow the right food nearby, and hire people to grow food and live lifestyles that promotes excellent blood quality. This can be a model for other villages to adopt. 

Maybe pay them by blood type and specifications (though that might cause class-ism within the blood farm). 

Seriously...Then MILK farms. HUMAN milk.
gpt
1. Because you are basically making them commit to something that's really invasive for life. If you're looking for someone with the perfect blood, you need them to live their entire lives according to rules prescribed by a specialist. You basically tell them to sign away their right to choice for money. That's a terrible thing to do.

2. Because humans have a right to decide what to do with their bodies. You can't contractually obligate someone to give you a part of his body, they can only donate it if they *want* to donate it.

3. Because commercialising blood transfusions creates a *huge* incentive for crime. We already have a horrifying amount of human trafficking in the world, imagine if people's blood became a valuable commodity. The weak and defenseless would be picked right off the street and bled dry, they would literally be worth more dead than alive. And where does it end? Look at animals. A pig is definitely worth more dead than alive, because they are bred exclusively for meat. And look at the lives of pigs today, they spend all of it being prepared for slaughter. Not many people in the world give a shit about pigs' rights, because who cares? They're going to be killed some day anyway. Now imagine if we treated the poorest, least educated human beings that way. We'd be a terrible, terrible society.

4. Because wtf, man, who wants to live their lives like that? That's just terrible.