We do a lot of crazy crap in the name of invisible gods. What's to say an alien race wouldn't get it in their heads that it's their sacred duty to their chosen

We do a lot of crazy crap in the name of invisible gods. What's to say an alien race wouldn't get it in their heads that it's their sacred duty to their chosen deity to fill every planet in the universe with their greatness, exterminating all the impure in the process? I have no problem believing the equivalent of the Daleks or the Ori might one day demonstrate a variant of the replicator hypothesis at our expense. Why must they have a coherent logical basis for all their behavior? We certainly don't.