Businesses are only able to grow to the size of amazon because of the exploitation of the working class' labor and government subsidies. Minimum wage and unemployment aren't an artificial constraints, they are things that workers have exercised their collective strength in to win concessions from their employers via labor organizing and collective action. It's the same reason we (generally) have an 8 hour work day, a 5 day work week, holidays off, safety requirements, workman's comp, and child labor laws to name a few things.

Edit: fixed typo.