The Catholic Church does not operate under a 'charter'. It was commissioned by Christ, Himself.
Mary is not an icon. She is the mother of God ... would you disagree with this?
All devotions to Mary and the saints ultimately glorify their Creator, who made them what they are. Could we possibly praise the Mona Lisa without praising Leonardo DaVinci? That masterpiece certainly did not paint itself! Even so, Mary is God's great masterpiece, and all praise given to her is praise of Her Maker.
When Elizabeth praises Mary, saying "Blessed art thou amongst women", Mary immediately replies "My soul doth magnify the Lord..." (Luke 1:42; 46). All the devotion which we offer her redounds to God's praise and glory.
An inscription at the Church of the Annunciation in Nazareth, dating back to 200 A.D., says "Hail Mary!". This is very early evidence of prayer to Mary.
The Sub Tuum Praesidium is another early prayer to her:
We fly to your patronage, O holy Mother of God.The Hail Mary also originated early on, since most of it comes from the Bible. This later became one of the prayers of the Rosary, along with the Our Father, Glory be and Apostle's Creed, all of Biblical or early Christian origin.
Despise not our petitions in our necessities,
But deliver us from all dangers,
O ever-glorious and Blessed Virgin! (circa 300 A.D.)
So Marian devotions clearly trace back to the early Church.
"Could we possibly praise the Mona Lisa without praising Leonardo DaVinci?"
That is a truly beautiful analogy.
It truly captures the meaning of the veneration of the saints, especially of the Theotokos.