I'm primarily a single stack shooter. I love shooting my skinny gun. I think the reloads add a fun strategic aspect to the game. I'll never stop shooting SS.
BUT....
Some days I just want to be loud and obnoxious. Some days I just want to see how fast (literally) I can pull the trigger and still hit the target. Some days I don't want to bother reloading, just burn stages down without worrying about it. Some days I just don't want to pick a single piece of brass. For THOSE days I have an open gun in 9 major.
Sometimes you just need to do something totally different to keep from getting burnt out.