Are we as kids really not supposed to demand anything from our parents?

Hi.

And if they either refuse, or don't do something straight away or don't act in a friendly, relatable and optimistic enough a way, is that, besides it being in their right, normal and the way to go, even if we do not welcome it or it doesn't make us feel better?

For example, can I say to my parents to do say a home renovation? Or buy me a new table, especially since I may have one and they may not have time or money to buy a new one at the moment, for various reasons? (Keep in mind we are not all millionaires with unlimited money spendings and we can't afford to always buy stuff on a whim.)

What about getting a new car? Painting a ceiling? Putting new wallpaper to replace old one?

Point is, we can ask yeah but often, besides it not being allowed or encouraged, demanding does NOT "work" and they may refuse or create some kind of domestic scandal if they feel we are being too demanding.

Here's another thing I sort of wonder. Lots of other people, maybe not rich, but native Brits (or Europeans or Americans etc) tend to have nice new wallpaper, well painted ceilings and even modern technology and entertainment items like new games consoles, TV, working internet, bright lights and whatnot. And we, not poor but not say millionaires, do NOT. Also, my parents may NOT be bothered by it and live happy being middle class and with homes without super duper decorations. I, their RELATIVE, may NOT be but they do not always fulfil my material desires like that, and in a lot of cases, I have to take no for an answer.

So, are we really not allowed to demand from parents that type of stuff as anything else? And if so, what can be done about it in short time, cheers.