Well, and religion in japan tends to syncretism anyway; the whole busshin-whatever era left an impact. There’s a big buddhist temple compound in Asakusa and one of the main halls is a Shinto shrine honoring the builders of the Buddhist temple. So.
But there are less friendly groups as well; some jodoshin and nichiren are more antagonistic to other sects. In the past of course there were some wild times, armies of warrior monks and so on...