Yep. I've seen it in some other industries as well, particularly with auction markets like AdWords. One company will figure out a novel PPC strategy that pays out considerably more in profit than than it costs to acquire a customer. If this strategy also scales, it's a license to print money for a time. Problem is, competitors notice and mimic the same strategy, bidding up the price of the ad units in question (keywords, what have you) until it cost of acquisition is very close to the lifetime value of the acquired customer. It's not so much that the competition buys up all the inventory (although that happens if you don't pay attention) but that the price of the good inventory soars for everyone. So more value gets captured by the publisher of the ad units and less by the buyer.