Joseph,
I have, thankfully, never been to a non-Jewish wedding. I suspect that what they do is substantially different than what happens at frum weddings. At frum weddings, the couple comes in together usually at a door that opens to both sides of the mechitza, and then they immediately go to their respective gender’s side. I can’t imagine anything like that happening at a non-Jewish wedding. Maybe ask a non-Jew who has been to a frum wedding if this it is similar to what they do.
I am also skeptical that they do the “now for the very first time” shtick. Because for them, after the wedding ceremony they are fully married, so when they come to the dance hall it isn’t the very first time.