Many players find SP’s easier to control (and for a lot of players the BH is more of a controlling shot)
Potentially a faster/more direct shot (if the pimples are used properly)
To add variety of spin (as compared to using the same rubber on both sides). Maybe they even twiddle their bat during the rally or during serves to try and mess up the opponent.
Maybe they’ve just always played that way (not everyone starts out with double inverted)
Perhaps they naturally have more of a flat hit. This is the reason why Matthias Falck uses SP’s on his FH, but no reason why the same logic couldn’t apply to thd BH.
Maybe they also play hard-bat and don’t want to diverge too greatly from that.
and probably loads of other reasons other players can come up with too!
Yes, those are the answers I was looking for. One more thing that helps is the large difference in spins from BH to FH. I switched from inverted to LP and played for 5 years but found it was hard (for me) to attack and the LP spin is too predictable for many advanced amateurs.