Okay, it's not insane, it just breaks from a convention followed by practically every programming language (and every logic / engineering / computing course) where integers can be interpreted as booleans. And that might be okay if there's a good reason, but the reasons given are pretty awful:
Ruby is one popular example of a language with a truthy zero. This is to allow the use of truthiness to detect the presence of a value (as long as the value isn't false), even if the value is zero. Say I wanted to allow an environment variable to override a value in my code. I could do something like this:
Dissimilarity for no good reason is, well, maybe not insanity but plain old dumb. Unless we're talking fashion not software projects, hence the "vanity" classification.
https://news.ycombinator.com/item?id=11852434