Speaking as someone who controls an indie trader character, indie traders don't necessarily go all over Sirius. Carrie, for instance, is Bretonian, and thus doesn't want to go near Kusari for fear of getting her head kicked in, she doesn't particularly want to deal in any unlawful activity, and the Liberty-Rheinland embargo prevents her carrying stuff directly between liberty and Rheinland. Indie traders aren't always these go-where-you-like, trade-what-you-want super-moneymakers. They have self-imposed restrictions. Or probably should, in any case.
*is for generic Trader IDs*