Yes, we know . . . the question is, “Why not?”
Because there is no “Three tiers of devotion” and the asking dead believers to pray for you is witchcraft as practiced by Saul and condemned by Samuel. (Notice I didn’t say that Catholics pray to the dead as they are often accused of doing)
Mary was a simple human woman, she was favored by God but she was not sinless,divine or in any spiritual way special. She also was not assumed into Heaven. Indeed you can see her tomb near the ancient city of Ephesus I believe. The Eastern Orthodox church knows where she was buried.
That said she was the human mother Christ. She has a special place in history and in the hears of Christians where she is honored but true Christians do not believe in the immaculate conception of Mary.