Bypass the middle man

What is the deal with catholic saints? Why do people choose to pray to Mark or Paul or Mary when they can talk directly to God Himself? Jesus said in Luke 11:2-4, "When ye pray, say, Our Father which art in Heaven, Hallowed be thy name. Thy kingdom come. Thy will be done, as in Heaven, so in earth. Give us day by day our daily bread. And forgive us our sins; for we also forgive every one that is indebted to us. And lead us not into temptation; but deliver us from evil." Notice to whom the Lord told us to address our prayers, "Our Father which art in Heaven" - Jesus is not talking about your dearly departed dad - He's talking about God. I just don't understand the point of praying to or through a saint.