After I got engaged, my sister gave me a copy of Emily Post's Etiquette—the 1950 version. It was half joke and half research, fascinating to comb through its musty pages to learn, for instance, how to introduce myself to a reigning sovereign should the Queen of England deign to attend my wedding. ("Mrs. Jones bows and, if the king offers to shake hands, Mrs. Jones bows again deeply as she gives him her hand.")
It's hard to imagine what Post herself, the queen of manners and doing the right thing, would say about weddings today. Wedding registries didn't even become de rigeur until a bit later in the 20th century. Up until that time, wedding guests chose from a socially prescribed list of household items—candlesticks, trays, china, and so on. The point of a wedding gift was that it was freely given, like all the best gifts are.
Now, of course, registries are the norm. Brandishing bar code scanners in department stores and clicking off Amazon wishlists ...1