Sorry, but sometimes people really do just vote against there own interests because they've been convinced of things that are wrong, or they misunderstand something. I expect you could even think of some examples if you tried.
And your whole post is just wildly making assumptions about someone you don't know: - "thinks of others as robots..." - "Everyone in the world must, as some precondition of the universe, be interested in all the same things" - "He cannot imagine that people external to himself have any real interests at all" - "this person tends to think of those others as malfunctioning" - "...it could be some sort of existential crisis as far as he's concerned" - "How could two competing interests even exist in a sane or fair universe" -
Perhaps you could have some faith? I doubt you've never voted for something you came to regret.