Why dont't people like Irish Traveller's?

i was watching a tv show called gypsie weddings....but i only seen it closer to the ending. And the bride was talking about how she gets rejected by a wedding planner wedding receptionist etc. ....well i dont understand why don't they like the Travellers or "gypsies"......and i still don't really get what they are because even though they call themselves travellers....they dont really "travel" anymore...or do they....i am totally confused.