Sir, I've bashed Apple a lot because I think they're a company that releases vastly overpriced products, but... The reality is, producing a major product line in the US is likely a quick ticket to a small profit margin or a failed product.
We all know that the cost of labor in the US would either drive up the cost of the product significantly, making labor one of the most expensive factors in production, or cut the profit margin to ribbons. What they would be banking on is that Americans would see the higher price and buy because of a "Made in the USA" sticker with a *much* cheaper Samsung or other branded phone staring them in the face right next to them. It's true that a number would, but, you mentioned "stingy, greedy mofos" about the corporations, and you give the common American *far* too much credit. They are every bit as stingy and greedy, and if you don't believe it, just look at the success of vendors who market things almost exclusively made by cheap foreign labour. Made in the USA goods were always there, but people gladly bought Walmart crap to save a few bucks and watched local vendors selling American goods go down in flames. Now those made in the USA goods are gone and people are pretending like it's all the evil corporations' fault for giving the consumer what the consumer voted for with their wallets.
The reality is, the patriotism market is saturated, and it was never that big to begin with. When people vote with their wallets, they would rather wave around an extra few dollar bills they saved than an American flag. These corporations are greedy, yes, but they aren't stupid - and they know what you either don't know or aren't admitting - that the common American will gladly buy Chinese when no-one is looking, even if they wave a flag when someone is, and they are every bit as greedy as the corporations.
You pair all this with the fact that there are a half dozen companies lying in wait for the big dogs to do something as stupid as expecting patriotism to sell products in the face of better prices and Apple knows that the epic blunder of large scale American production is one they can't afford if they want to stay in the top spot.
Besides, those sweatshop workers work a heck of a lot harder than Americans while expecting far fewer benefits. Frankly, the modern western world worker is an entitled brat, and you don't pull a profit trying to sell goods made by people who expect the world given to them on a platter made by people who expect the world given to them on a platter.