who is going to pick the cotton?

Is a phrase that originated during the fight for abolition of chattel slavery in the mid-19th century in the USA. Southerners would argue that they couldn't abolish slavery because it was needed to pick the cotton.

Since then it has been used rhetorically to show people how dumb their argument is. It doesn't matter who picks the cotton, its immoral to keep humans as property, the market found a way. The same is true with using an imaginary line to control people.