OK. But then there's also the fact that bacteria are everywhere, and that our own bodies are teeming with them.
Bacteria themselves are not a problem and don't cause disease.
The germ theory of illness just doesn't make sense when you think about it. Even Pasteur said, on his deathbed: "The Terrain is everything, the germ is nothing."
So do we need to worry about drinking urine that is more than 3 hours old? I myself am not worried.