I believe that the focus of hybrid8's question was on the cultural differences between the US and many others around the world as opposed to cash gifts at weddings.

My wife is from Laos and we do alot of entertaining. She is constantly shocked when an "American" guest asks if they should bring anything to the dinner. She believes that they should already know that there is an unspoken "list" of things to bring to such a function; wine, champaign, flowers, etc. She also doesn't understand why some people bring nothing to parties or dinners that someone hosts.

Our non-American guests (Europeans, Asians, middle-easterners) all seem to bring something to dinner. Elsewhere in the world, it is conisdered rude to not show some sort of appreciation for the effort that the host makes aside fom a simple Thank you.

In our wedding, we did not make a registry and we announced that if anyone wanted to give us a wedding gift, that it had to be in an envelope - a suttle reference to monetary-only gifts. Of course, we were already well-established, so a registry wouldn't have made sense.

It is mainly cultural (which is evidenced by some of the responses here). Imagine calling a Japanese man cheap for not leaving a tip in a restaurant here when it is rather insulting or irritating to tip in Japan.

The funny thing is that is seems to be a contemporary cultural thing, because when we invite older Americans (60+ years old), they always bring smething.

Personally, I like the idea of bringing something to dinner/weddings. It seems like the right thing to do.