FM antennas are indeed placed as high up as possible on these towers, but the tower itself, being a guyed model and not freestanding, does come down to a "ball

FM antennas are indeed placed as high up as possible on these towers, but the tower itself, being a guyed model and not freestanding, does come down to a "ball and socket" joint at the bottom, which allows the tower to move around slightly under the tremendous pressure of the guy wires yanking it down to earth. Apparently there's a deep 25'x25' slab of concrete underneath that holds the socket the tower rests on.