Iran's beef with Israel is not because they care about the Sunni Palestinians or Palestinian land rights or something like that. They certainly don't want peace, they want Israel wiped off the face of the earth as a religious goal in itself, and for being the only non-Islamic country in the Middle East. Any concern expressed by Iran for Palestinians is purely for propaganda purposes: It's easier for Westerners to sympathize with than saying they'd like to destroy Israel and kill all the Jews simply for existing.