You know what the biggest reason this is a terrible idea is? It doesn't even accomplish anything. Consider SatoshiDice, the biggest "offender" when it comes to noneconomic translations. All they've got to do is have people send an extra 0.001 BTC with their bet and send it back either with the winnings or alone if they lose. They could even throw in an extra satoshi for tradition sake.
The assumption that this is directed at SatoshiDice, or any other single entity, is fallacious.
The postulation that this doesn't accomplish anything is simply incorrect.
This patch removes the ability to CREATE outputs (using standard transactions) that cannot be economically spent. It also removes a "magic" number from the source code and introduces greater configurability for miners.
The result is that far fewer people (newcomers especially) will end up with a wallet full of outputs that they cannot spend without incurring a fee greater than their value.
In other words, the change addresses a real, existing problem and enhances the experience for newcomers.