a chinese wedding dinner is supposedly a ceremony to show to ur frens and relative that u are married, who is ur wife. It's just like a stage for u to tell ur frens and family, hey guys, she is my wife, we baru marry.
So in return, those that attend usually help back the bride la, financially. U think cheap kah mau do wedding dinner. Those that attend is the bride's fren and family ma. So u help me, I help u la.
Bride treat u as his relative or fren, baru invite u go. So u help him back and repay little for the dinner lo. it's common courtesy for a chinese wedding dinner. Up to u how much u wanna pay.
just from the bride's pov, this dinner is to let my frens and relative noe that I have married this gal.
from the guest's pov, ok la, the bride respect me as his frens/family, appreciate his effort to invite me, hence help with the dinner bill lo.
ok, this explanation good. the last sentence .... so now its worth the money to give them hehe