I am ethnic Chinese, and I do not consider cash as an appropriate gift in casual situations with friends and colleagues -- unless there is an understanding that the recipient is under financial strain and can really use the cash. Whereas a cash gift is defacto mandatory for events such as funerals and weddings (in the communal nature of Chinese culture, the attendees show respect by pitching in, even a minuscule amount, to help pay for those important life moments), giving cash for daily use insinuates penury or financial inferiority onto the recipient and does not give them face to reject the gift.