Having more fuel in the tank of your bike or carrying a jerry can or even going hardcore and installing a plumbed-in auxiliary fuel cell has no affect on anyone's bladder or belly grumbles.
I'm always surprised when the topic of extra fuel range is countered by somebody referring to their bladder. More specifically that their bladder can't last as long as the fuel
I often run 42 litres and I can stop anytime or anywhere I like for a leak or a bite to eat during that fuel leg. I don't have to stop at a gas station for that.
Similarly, when I do have stop to fill my tank I don't pace back and forth for half an hour waiting to get hungry or feel the urge for a leak.