Where does the top's angular momentum get transferred to? Does it very slightly change the angular momentum of the table, and then the angular momentum of the Earth?
Conservation of Angular momentum applies only when you don't have any net torque on the system. For a spinning top, the frictional force between the top and the floor would give it enough torque in the opposite direction so as to make the top stop (this is much like how a block loses its linear momentum due to friction when it slides down a plank). As far as the energy goes, it gets converted into heat, sound etc. Of course if you took an atomic point of view, you'd see that the angular momentum of the top slightly changed the angular momentum of the molecules of the table. It would also have changed the angular momentum of the earth. But such effects are hardly noticeable. This xkcd comic is relevant: