That is true but then your average drunk would still choose the path of least resistance which is usually the nearest bush, wall or tree. We are genetically wired to look for the easiest solution which would of course be peeing wherever we are when nature calls. The only thing that stops us from exhibiting this behaviour when sober is inhibition. When alcohol numbs our inhibitions and sense of risk we revert to our most primal selves and in some cases that means we piss in places we should not piss in.