As for examples in current synths, I would say that given any synth of a statue or a person standing still, a simple use case would be to zoom into the face or head of the statue or person.
In some cases of statues the inscription, information plaque, or pedestal may be of equal interest.
In cases of spins with a number of objects (a yard, a still life, etc.) you have essentially captured multiple spins. By giving the user the ability to lock onto only the tree or only the rose bush or only barbeque grill seen in the yard, you enable users to harvest more value from their viewing experience without stopping and zooming in and out with every photo. Similarly with a large model set or a fruit stand, enabling us to zoom in on each piece of fruit or each component of the model lets us extract many little spins, even if we're seeing the same angles as when zoomed out.