When Julia Zaher, the owner of a company that makes some of the most popular tahini in Israel, made a donation to an Israeli gay rights group recently, she saw it as an unremarkable act. “When I see people in a tough place, I always like to help them,” Zaher, 65, an Arab citizen of Israel, said in an interview. “If everyone turns their back on this community, who is going to help?” The backlash in Israel’s socially conservative Arab community was swift and unforgiving. Activists called for a boycott of her company, Al Arz. Videos circulated on Facebook and Twitter of Arab shopkeepers pulling Al Arz’s tahini from their shelves and throwing it in the garbage. An executive at one of the largest Arab-owned grocery chains in Israel, Al Mashadawi, said it was considering dropping Al Arz from its 14 stores.