Something like why to Catholics revere saints? Isn't that idolotry?
No, Catholics do not worship saints. We honor them and venerate them but worship belongs soley to God.
My small piece here on the saints thing is that, as Catholics, we acknowledge the "community of saints" and that from those saints we ask for intercessory prayer. And that is simply asking them to pray for us in a way that is no different than any other person asking his friends and family to pray for them. That even applies to the Catholic prayer, "Hail Mary", which is also a request for intercessory prayer and NOT a prayer to her.