Just a thought in general, those verses in Matthew. 24:37-39, in particular verse 39 seems to indicate to Me that events in general were what's perceived as "Normal" everyday affairs like Marrying & being given in Marriage, like the custom of Men giving their Daughters in Marriage, giving away the Bride, so to speak. I mention Verse 39, because it says they "knew not" UNTIL the Flood came and swept them all away. Nothing seemed to be happening out of the ordinary to most People, just like Today, that would convince them of their End, sorta like Today. Most of the "Christian" believers of the many & varied Denominations still, at least officially, would not look upon Homosexual Marriages as the Normal everyday affairs of People, so they "knew not" or one Translation uses the phrase: "They took no note," UNTIL the flood came & swept them all away, seems to indicate to Me, that a high percentage of People wouldn't be fooled by Gay Marriage, because they wouldn't consider that as being the usual or "Normal" everyday practices, so as to be fooled or "knowing not" until it was too late.
Applying this to Gay Marriage, IE- Given in Marriage is an interesting take on the passage, but only seems plausible through implication, but doesn't seem explicitly clear in examining the passages from Matt. 24 and Luke. 17.
Just My Take, Samson.