Plain and simple, companies can't just move back to the stateside. The consumer is driven by the lowest-cost denominator. Keeping in mind, when something is so much as just a few cents less than the product next to it on the shelf, that appeals more to the consumer in most every situation. Companies packed up and left because everything costs considerably more to manufacture in the USA, so profit margins drop and/or product prices increase. If there are a few companies that charge "X" amount for a product that they all produce, and then two of them leave for China and setup shop. That places those companies in a position to now charge less than the sole survivor who can only go as low as breaking even. Then those other two companies make shareholders/investors happy at record profits, while the other company is left to explain to their shareholders why they missed the mark as a "sell, sell, sell" mentality develops as company value drops.
It's an ugly situation but all too real. I give huge credit to the companies to move back to the USA because face it, it's a VERY large gamble - but a commendable one. Packing up and leaving with the promise of higher profits was the easy part, coming back is the real challenge.
As for Apple, it's obvious their profit margins are quite healthy, but hey, it makes their investors and shareholders very happy, right? I'd like to point the finger solely at them, but they aren't the only ones outsourcing like this (insert almost any company name) and charging a healthy price for their products.