I've never been fond of the song we're talking about here. I find the chorus twee and the melody too wholesome. According to the DT, where it appears as Gypsy Rover, it was written by Leo Maguire.
Leo presented a programme for many years on Irish radio sponsored by Walton's, a well known music shop in Dublin. He finished up every week with the advice "if you feel like singing a song, do sing an Irish song".
Irish music wasn't particularly respectable at the time Maguire started (the 40s or 50s?)and what he's written here, it seems to me, is a bourgeois version of an old story.
The second last verse makes it clear that the man she runs away with is indeed wealthy, and not a gypsy: "At last he came to a mansion fine...". So all's well then, etc. The whole message has been transformed compared with the variants mentioned by InOBU.
Davy Faa, also in the DT, is much more complex. Have you ever heard a more poetic way of describing a rape ("Twas there he took the wills o'her afore she was won awa'")? Social realism in Scotland obviously didn't begin with Trainspotting.