Why Hong Kong ppl so rude?

In restaurant everyone shout at the top of their voice

Order food ask to hurry up when I inquire about the dish

Then throw the dish on table

Their life is fast paced but in Japan also fast paced yet polite

Can hear shouting
Lei GAO Chor ah???
Chi seen
Lei ho mo ah??

Worst is they are rude coz i don't speak Cantonese
Speak mandrin they think I'm PRC so then I speak in English but they don't understand?

They think I'm PRC??? How

Me too. I still remember they pour the oyster sauce to the BBQ pork with wantan mee. The taste is awful and it is expensive as hell.

The only food I can accept is the fast food, BBQ duck and the milk tea.