Yup. My reaction exactly (and I've read all of @Silver/'s spoilers: thank you very much for them as they're extremely enlightening). It is utterly lousy that using/not using the tadpoles has no impact on anything other than whether you get awesome tadpole benefits or not.
@SoulfulAzrael, I completely agree with all of what you've said. The whole "being good is its own reward, and one shouldn't expect anything for being good" is utter B.S. nonsense. It does not have even a modicum of logic to it, because this is not real life. This is a game. And in a game, everything is about gains and losses, costs and benefits, rewards and punishments. It is truly pathetic game design, based on an agenda to get people to accept that doing bad things is okay.