Because people's digestive systems work differently. Additionally, some people might be sensitive to certain foods - while others aren't.
because they fart
It's the small amount of methane in everybody's farts. Some people produce more than others.
Some people need more sleep than others because of their age and what they do.
Possibly not as much as some people ask totally inane questions
Yes, for some people.
Some people are naturally "genteel".
That really depends on the individual. For some it may, for others not so much.
Most people do, some more then others.
Some people need more sleep than others for several reasons. Some people are busier and need more sleep and some may need more sleep due to genetic reasons.
Because some people produce more oil in thier scalp.
Some people have different sense of comedy. some will think they are funny, ehile others will be more machure
Family was highly valued by the Blackfoot Indians. For traveling, they also split into bands of 20-30 people, but would come together for times of celebration. They valued leadership skills and chose the chiefs who would run their settlements wisely.