Hollywood overlooks defecation in films.

I was watching Chronicles of Riddick today and during a scene that involves a lot of running though deadlands and wastelands, trying to escape the bad guys, a thought came to me.
What if Riddick feels like shitting while climbing that cliff face? Like right now?! Like not later but RIGHT FUCKING NOW!!
What then?
Since movies try real hard to look real and to try and keep you grasped the directors should think about this important factor when dealing with humanoid characters. Humans need to defecate.
What really annoys me is that never in a movie do you see a character escaping from the bad guys but stopping midway to shit. You dont have to actually show it but can suggest it can't you?That really fucking ticks me off! If youre gonna make me believe that he is in trouble and that the bad guys are gonna catch up to him, thats trying to fuck with my emotions directly isn't it? Then if your'e doing that job so well, why are you being unrealistic about shitting and peeing?
Do you know how hard it is to run when you feel like you reeeealllly gotta go? There is no way that someone can run or think or do anything but drop his pants down when the shit feels like it wants explode.
So when Riddick is climbing that cliff face and he HAS to shit, you need a dialogue saying that
"damn i gotta shit!, ugh but i'll do it after i climb this piece of shit" After he climbs it he goes behind a rock. Cut. Thats it! Thats all that im asking for you bs hollywood directors!
Anyways just had another thought,
What if Batman wanted to shit in the middle of a fight?
You think about it.