Yes, this was used on a wedding invitation and when we inquired about it, we were told that this is etiquette. Being married 45 years ago, my wedding etiquette is somewhat rusty to say the least, so any light you may shed on this question would be appreciated.
Please re-post in the wedding invitation category and include all of the information we would need to answer your question, including the invitation wording. Top Wedding Questions Forum Moderator - "Write your sorrows in the sand, your blessings in stone".