It's not explicitly said that the reasons for the public devotional is to dissuade the couple from an embarrassing betrayal of those public vows. To the author, being explicit would mean saying "and we say all this so we'd be more wary of breaking up, given we just told all of you how much we're going to stick by each other."
The article says: "You consider telling everyone... but decide it’s better not to make that explicit."
I'm asking for examples of something people "consider telling everyone" but decide it's "better not to make that explicit."