"Don't do this nice project that feels warm and fuzzy to you" is guaranteed to provoke a strongly negative reaction in the vast majority of people hearing it, and there's the obvious double standard (which people won't hesitate to point out and make you look stupid) of objecting to such charitable projects but not objecting to somebody buying a movie ticket, say. Besides, buying fuzzies is perfectly fine.

And that's even without the status considerations that paper-machine points out. People think we look weird already. Attacking a high status individual famous throughout the Internets isn't going to make that better.

At a guess, the Oatmeal is raising new contributions from people who were highly unlikely to be donating to charity in the first place (selfish young geeks participating for solidarity with their social group at the order of their leader); attacking it will probably shift very few dollars to better charities and will be very expensive for us. I think there's an XKCD comic on this, actually...

I doubt LW has the social capital necessary to intervene without considerable backlash. Oatmeal is the Randall Munroe of 2012.

My first guess would be no, given that any amount of capital significant to the project (which seems like it would just generate warm fuzzies anyways) is probably a crapload of dead kids.