Why is it difficult to follow rules?

How guests have to behave?
When you visit somebody else, how do you behave at their house? Do you do everything they ask, like don't do this don't do that, don't do it like this, do like that? I certainly do.

Why some people are so difficult to understand what you want them to do, or not?

Older people are even more difficult to accept the rules, maybe because they already lost part of the brain or because they might think they don't have to obey anybody.

Our flat is almost or a little bit more than a 100 years old, when you walk on the floor we kindly ask people to step on certain parts of the flat because it makes a loud creak. So you just have to walk in the side of the corridor, close to the wall and not step on the door treshold.

I don't understand how difficult this is because I can walk without a noise, maybe it has something to do with the anorexic 40 kilos I weight. We kindly ask for people not to throw hairs on the shower box, because it is bad for the pipes and our foot, since the dirty water can't follow her way down. We kindly ask people to throw the toothpaste dejects in the sink, and not on the side or on the wall or on the mirror.

Please don't get me wrong, I really like to have guests, we always used to have some. But why is it difficult to follow the rules?

Am I too picky or am I just rude?