I grew up in the Lutheran Church which simultanelously tries to ape the Catholic Church and still assert any differences it can. My father was a very intellectual Lutheran pastor, big into all that theology jazz.
In general, the Lutherans and many other protestants consider the Catholic Church's relationship with Mary and the saints to be idolatry. Early protestantism was founded on the concept that humans can supposedly have a direct communication with Jesus/God, and do not need various holy middle managers interceding.
In my collegiate days studying literature and history, I learned about many backwaters of the world, in rural Latin America, rural Eastern Europe, etc., where Catholicism is practiced in such a way where an observer could not escape the conclusion that Mary is actually the object of worship.
That is because in earlier times the Xian missionaries substituted Mary for the fertility goddesses that had been worshipped in these places. The intellectuals of Catholic Church itself believe that this is in effect happening in these places but as long as people give money and refuse to wear rubbers, the church shrugs it off.
I often wonder wether it is really possible for the majority of humans to worship and a gaseous, invisible, omniscient, ominipotent being who does not like to be depicted in graven images. Certainly the Catholic Church has wrestled with this, and that is one of the reasons for the pantheon of saints...saints can be visually depicted, and a human can hold a mental hologram of the saint in his brain...Yahweh is harder to fit into a human brain.
This leads to the meta-question...all these people who claim they are Xian...what are they really worshipping? A father surrogate? A fertility goddess? (Mary!!!) Do some worship their own ego or Will to Power?