I've never heard any songs about oppressing poor people or poachers, except they are taking the side of the poor people being oppressed and the poachers.
Gypsies and the like, well, I have heard a few songs where they are seen as the outsiders and suspect. But more often in the songs where Gypsies come in, the song tends to be from their side.
So far as this song is concerned, it's maybe a bit more complicated than has come out.
My understanding is that there are two parallel songlines in the tradition which have come together in this version.
One is the song about the lady eloping with a band of Gypsies, and the husband (most times) coming after her. Sometimes the Gypsies end by getting strung up, sometimes the ending is left open - either way the lady is clear enough that she would always choose the Gypsies over her husband. (And there are some versions in which there is a suggestion that she was a Gypsy in the first place herself.)
And the other song is the one about the lord or the prince, or often enough the King of Scotland who makes himself out to be a Gypsy, because he envies the free life, and when he has a girl run off with him, at the end he reveals who he is.
Both songs on balance tend, in their various versions, to be on the side of the Gypsies, even if sometimes there's an element of patronising romanticising of the life.
The Leo Maguire song brings the two separate songs together and blends them. I've never really liked it too much, seems a bit too sweetened. Maybe it'd be better in the Irish version.
Incidentally I've said Gypsy here because a lot of the time in these songs they probably aren't Roma - while the word "travellers" has got so mixed up in recent years, what with New Age Travellers and that, and my understanding is that these days many travelling people prefer to avoid it. And of course "travelling" doesn't define people, it's often what's been forced on them. As a term, it's maybe a bit like migrant or refugee.