Am I justified in asking why you bought an iPhone when you could have saved a starving child with that money, and whether you think getting an iPhone for yourself is more valuable than saving a dying kid? If not, you're a hypocrite. If yes, that too tells something about you.

I accept utilitarianism. But I also think we're not born with a utility function. When I vote, I value it being an informed decision. If you ask me whether I couldn't think of anything more valuable than that, I'd ask whether you couldn't think of anything more valuable to do with your money than buying a smartphone.

To be honest, I don't vote. But many do and value their right to vote.