My BFF claims that in her her experience, sometimes the person in the more privileged group is in that relationship because they may have a secret conscious or unconscious need to feel slightly better than their partner. Or that the more privileged person assumes there may be more drama due to a bigger family or disadvantage of some kind and may enjoy the supposed excitement or adventure of this.
I’m not sure that’s really true, except maybe in the rarest cases.
What do others who have been close to situations like this or have informed themselves about it think?