Amazon might be a little bit like that: a fountain of wealth for Seattle (and check out real estate prices there if you think that's an exaggeration), but pumping that wealth out of all the rest of the globe.
But I see a weakness in this argument: Wal-Mart mostly displaced existing chain stores, which had similar wealth-pump effects -- and which had much higher prices than Wal-Mart, partially because they wanted higher prices but mostly because they didn't have Wal-Mart's hyper-efficient supply chain. And the old corner groceries and general stores had supply chains that were even worse than the previous generation of chain stores, and therefore even higher prices and even smaller variety...
So: you hear the wealth-pump argument, wealth pumps do sometimes exist, and I'm pretty sure the previous poster was accusing Amazon and Wal-Mart of both being wealth pumps; but I'm not entirely sure that that's what's going on with either business. If it is going on, of course, it's a problem. (Have there been any studies on Wal-Mart's effect on areas where it opens?)