It's an extra special touch with half of them labeled drug dealer when skooma is part of their religion. It's prohibition targeting a religious and racial minority.
Semi related: in the USA, marijuana came with Mexican immigrants, so a lot of the criminalization stems from racism and xenophobia. The same applies to Brazil, since it was typical to find natives and blacks smoking it.
If I remember moon sugar is part of the religion but people took that and refined it into the narcotic skooma. UESP says the Dunmer were the ones who refined skooma originally and that moonsugar is more potent for non-khajiit. So drug dealers from other lands take something they aren't physically adapted to consume, refine it, sell it, and malign khajiit as drug addicts for using it natively.
Like a teetotaler fainting at the fumes of a beer and calling you an alcoholic.
To be fair he may not actually be a rapist. He calls himself "defiler of daughters", but he's doing so in a theatrically rogueish list of reasons people would want to kill him, so it could just as well be consensual but the parents are furious about it.
However even if that is the case, he actually is also a self-described murderer and thief who implies that he runs a dangerous gang of some sort and regularly has people trying to kill him