This actually is a bit interesting to me. Any fusion that hasn't been out of necessity seems to have an addictive flavor to it, excluding Stevonnie. Even a fusion like Malachite made the two involved obsessed in very bad ways.

Is it possible that Homeworld banned fusion because of this? Maybe some fusions were like Sugilite and went rampant. Or some Gems were forced to fuse, like Malachite, and it was banned because of that. Maybe both?