Horrible-if what you're doing is fun and not hurting anybody, why is it wrong? If what you're doing is knowingly wrong and hurting somebody else and you continue to do it you're a giant asshat.
I don't think I'm reading the quote the same way as you, since I don't get anything about harm/non-harm out of it.
My interpretation: I think the quote isn't meant to be taken literally, but rather to express the natural human tendency toward existential angst over purity -- and our perpetual unwillingness to do it
quite yet.
In that, I think it's quite clever. But maybe I'm projecting and totally misconstruing it.