Yeah but factions WANT guns. Guns aren't a totally legal racket either class 4's aren't legal. I literally can't recall the last time gun rackets have transferred. Guns are also sold illegally all the time the amount of felons with guns is off the charts.
Attachments aren't fully legal either they can be sold just as illegally as guns. Attachment factions are also dead as fuck I've never seen an attachment get sold legally or illegally after the Cassano trial.
Casinos don't have to be fully legal either illegal gambling is based.