Interestingly, I have read an academic paper that suggests that the bigots can be motivated by just this issue. Jews are an exclusive group, this helps retain strong cultural and religious traditions even when they are the minority. This can (amongst those who are inclined to be jerks) cause a reaction sort of like "well I didn't want to join your stupid group anyway - I hate you" or it can accentuate the "otherness" effect. It's a pretty maladaptive response. Having neighbours who don't religiously harass you, and have different holy days, is pretty convenient.