My non-European partner gives money to their parents despite being fairly middle-class and fiscally stable. You're right, it's cultural - theirs expects grown children to contribute to the parents after spending their childhood paying for them. It's an investment into the family unit as a whole, as the family will support you beyond what the state welfare could provide. Had a car accident and need some money? The family can help. Want help with a deposit for a place? The family will contribute.
In my waspy American family, nobody asks for help or even would let it be known they are in need. It would be an embarrassment. We are individual capitalist and you must not be weak!
That said, there are a few deadbeats who try to take advantage by always being in need. But only to finance their life of leisure, not real need.
