That said, I have gone and visited many Catholic Churches and there are many where a big statue of Mary is on the alter and trying to find any hint of Jesus is like trying to find Waldo. As a Catholic, I also have visited many Catholic Churches, and I suspect the number I've visited is many more than you've visited. I have never seen a statue of Mary on the altar. We're you in the Catholic Churches during Mass? If so, here are some of the requirements for the altar during mass from the General Instruction of the Roman Missal:
306. Only what is required for the celebration of the Mass may be placed on the mensa of the altar: namely, from the beginning of the celebration until the proclamation of the Gospel, the Book of the Gospels; then from the Presentation of the Gifts until the purification of the vessels, the chalice with the paten, a ciborium if necessary, and, finally, the corporal, the purificator, the pall, and the Missal.
308. There is also to be a cross, with the figure of Christ crucified upon it, either on the altar or near it, where it is clearly visible to the assembled congregation. It is appropriate that such a cross, which calls to mind for the faithful the saving Passion of the Lord, remain near the altar even outside of liturgical celebrations.
There is no mention of a statue of the Blessed Virgin Mary and it is not allowed on the altar during Mass. Do you have a picture you can post, because I have a hard time believing it was on the altar, especially a 20 foot statue of the Blessed Virgin?