Saw this gem on the Dear Prudence column, thought it should go here:
Q. The Invitation That Wasn’t?: We have known “Joe and Mary” for years and their daughter is a few years older than our children. My husband and I recently received the following … something … from Joe and Mary: “Joe and Mary X along with Jim and Suzie Y would like to announce the wedding of their daughter and son Katie X and George Y on Dec. 1, 2014. The couple is registered at Target. They would also appreciate cash gifts to put toward large purchases for their new home.” It arrived days before the wedding. No time or location for the wedding. No other correspondence or invitation. Since it wasn’t a “save-the-date” card or an invitation, the only thing it could be would be an announcement combined with a gift solicitation. Is this normal? If so, what is the appropriate response?
A: Oh, yes, it’s “normal,” but the fact that people make explicit gift grabs does not make it right. You’re right this is not a notification of the happy news after the event with a new address (and possibly new name) that people sometimes send out, and which is fine. This is an explicit money solicitation. What you do is respond to this news with a card—just a card—wishing the young couple all the best.
Original link. It's the last one on page 2.