Does it have kuru? I'm only open to eating healthy human flesh in this scenario.

Also, if it poofs into existence from nowhere, is it creating matter out of nothing? It's creating something that still has usable energy in it, out of nothing? That could not only end world hunger and veganism, you might be able to use the newly-created corpses for fuel in some kind of power plant. Sure, you might have to go back to steam power to make it work, and sure, human bodies might not be the optimal fuel source, but if you're getting them from nowhere, that solves all our energy woes.

It also might make the planet gain mass, eventually, if you did enough of it for long enough. Hmm. Oh, well, you can use that to make spacecraft. Maybe. Or something.

That and blood pudding. And fertilizer.

I think actually, being able to poof human corpses into existence would be an improvement over the current state of affairs. It might still be sub-optimal, but it would be better.

Now I want to be able to poof human corpses into existence from nowhere. I also think maybe I should start a list of things I've said that I wouldn't have been able to predict that I would say if asked the day before.

Nobody said "free." The operational costs of corpse-poofing might be prohibitive.