Zoners are "lawful" by default, I believe. No, we're not allowed to hang out with pirates, attacking lawfuls. GST tried that.. phail. But "smuggling"...?
Those Zoners who choose to carry "questionable" goods run the same risks of fines, imprisonment, or more dastardly measures if caught.
I would venture that 99% of all cargo carried by all Zoners is "legal". However, there are just times when "running empty" on the return is not an economic option, sir. A wise man named Jay Simon taught me that.