I assume that you are referring to the reverse (finish) FH. If not, pls make a distinction.
Many players can easily generate more spin with it -- more topspin, often with a good dose of sidespin and sometimes some spiral spin. Some players, like Sharapova, often use it for a late contact -- instead of making contact even with the front foot (or forward of it), contact is made later (often, in line with the back foot). Some of Nadal's reverse FHs fall in this category.
Sampras primarily for hitting balls out wide when he was on the run. He could generate some great spin and angles with this use of the reverse. This is the use of the reverse that I show or teach to students.
Back in the early 80s (and late 70s?), the reverse finish was often employed to teach the topspin lob. Topspin lobs were not common back then and coaches often discouraged it. Lobs were hit fairly flat or with underspin. As rackets become larger, topspin lobs became more common. The reverse finish was often employed in teaching to show how to exaggerate the topspin on the shot.