If God Is Present All Around Us, Why Does the Church Teach Transubstantiation?

A listener named Lenny asks Father Dave about the Church’s teaching of transubstantiation. “I went to Catholic High School, and we learned that God is omnipotent, omnipresent, and omniscient,” he begins. “[Regarding] transubstantiation, we understand that the priest is bringing God or Jesus into the host. My comment, or my ignorant question is, wasn’t he already there? Like if he’s omnipresent, omniscient, and omnipotent, isn't it already that way?”