People who don't know anything about game engine programming just don't understand. It's quite obvious that given how "alien" a platform the 3DS is compared to the PS3, 360, and other systems it's not much being able to power it as it would having to create a whole new engine from the ground up. An engine that can run 3D non-stop, an engine that is optimized for the specific hardware specs, and an engine that can run at full FPS. Break that down into timing it would take someone like Epic several months to make that original engine, thus making it totally different from Unreal Engine 3's basic coding.
Break that down into licensing, everyone who wants to use the tech would have to fork out major cash just for that specific engine, not Unreal Engine 3, and that's where you start losing profit. Engines like Unreal are profitable because you can develop for the PS3, 360, and PC using the same assets and tools with minimal need for scaling...break that down into having to fork out a license of a totally seperate engine for only ONE platform, that would require as much if not more manpower to develop specific assests and code for just the 3DS, which means budget costs go up, and if the 3DS version bombs it's practically as bad as if the multi-platform version bombed as well.