Developer Kalid Shaikh has been banned from the iPhone App Store.  By conventional welfare measures this would seem to be a big blow to efficiency:

As the MobileCrunch article points out, a search at shows 854 apps by Shaikh. The majority of Shaikh’s apps seemed to be data on a specific subject simply pulled from the web without providing any other original or unique content. Most apps were priced at $4.99 and this banishment could represent lost sales of thousands of dollars per day. Shaikh reportedly has admitted that the goal was not to produce valuable apps but to focus on monetization instead. All of Shaikh’s apps have already been removed from the App Store and can no longer be purchased.

Perhaps conventional welfare measures would need to be amended in this case.  Note however, that removing one large supplier of what is essentially spam from the App Store will not affect the equilibrium quantity of spam.  (And this is not Apple’s stated reason for removing him.)