Why are most adults so mean to us kids and teenagers? Even my adult siblings yelled at me?

I mean yes it's rude to butt into people's conversations, but they don't have to tell at them. They have no right to yell. I asked my aunt about something. Then she said, "Sweetheart....STAY OUT OF GROWN FOLKS BUSINESS!!!"
Jeez I just asked a question and adults have to scold at us.
They can at least be nice about it. My dad would say, "Get out of our mouth, this is grown up business! You're a child. You don't know anything about life so butt the hell out! You miss need to quit being so damn nosy and you are hard headed. Stay out of our BUSINESS!!!!" Even my adult siblings told me to stay out of their business!
I wasn't being rude. God. Adults teach kids to not be rude and then they are rude to them.