I've heard of those things, Ajane, but only from Canadians - seriously. I don't know about the ethnic backgrounds behind it, but I've never heard of that in the U.S. I'm from a Southern U.S. family and there are definitely regional variations, but wow - if someone were to have a fund raising wedding party where I am now (California) it wouldn't fly! Showers accomplish the same thing, but the etiquette around them is that they are not thrown by the wedding couple, and that you don't solicit any particular money or gifts to attend them (and you would never invite someone to the shower who isn't invited to the wedding). Of course, the flip side is that people would hopefully never show up to a shower without a gift, but gifts are supposed to be optional - they are gifts, something freely given. I can't imagine going to a shower without a gift, but I can see not going to the shower because the bride is throwing herself a party and telling everyone she needs money for the ceremony.
Viva la diferencia, I guess!