Actually, this hatred was nothing special. They hated the Gypsies even more, and when it came to the Mongols, they fought some serious wars to keep them out. Same with the North Africans, Franks, Teutons, Greeks, Romans, and probably most others who ever thought to show up in Europe, invited or not.
The French government once undertook to destroy the Protestants by murdering them all. In fact, the French government still pursues that policy, although a tad quieter these days.
Europeans definitely have an attitude problem.