When the muggles started up Wicca in the 1930s and 1940s (and particularly when the witchcraft laws in Britain were revealed in 1951, thus allowing Wicca to be practiced openly and to spread) the Goblins saw the Purebloods looking down on the muggleborn asking about it, and the Goblins chose to adopt aspects and practices of Wicca to their magics and societal holidays.

This just makes the purebloods, and the magically raised, even more disparaging of the Goblins and dismissive of muggleborns asking after “goblin” stuff