On top of unit costs there is cost to stock in store, cost of the store's profit, etc. Let me ask you this, would you be willing to pay $10,000 for a computer Made in USA? Is the computer you are working on right now Made in USA, or are some components from China?
That's the answer right there. We can pay $1000 for a Chinese made laptop or $10,000 for an entirely USA made one top to bottom. What market is there for the eco and labor friendly USA one, and what is the chance that a company selling these would stay in business for even 6 months? Is the chance greater than 0%?
The easy (but probably wrong) answer would be how western import taxes don't have enough environmental/ethical component in them.
Too bad we can't be bothered, since we must protect corporate profits at any cost.