My mother knew a gypsy reader, who taught her alot on cartomancy, and my mother read with playing cards. she can read with tarot too, but I think she prefered the playing cards.
My grandparents knew some gypsies who also read cards, and they could also do palm reading, and crystal ball reading, tea leaf readings, etc. my grandmother visited them often--they were friendly with each other and often read for each one another.
however, I think like with anyone else, it was something separate from them being a gypsy. I could be wrong---but my family also knew gypsies who didn't do palm reading, cartomany or crystal ball readings.
My own family is of Irish descent and these different ways of divination was practiced among many in my ancestry---but we also knew and had Irish ancestors who did not practice divination. Just different strokes for different folks.