Smuggling

Smuggling is the clandestine shipment of illegal goods, or even clandestine shipment of legal goods to prevent taxation or some other impediment.

Smuggling thrived under the Galactic Empire, for there were many items which the Empire wished to control for various reasons. For instance, spice: the Empire didn't necessarily care about the physiological repercussions that spice might cause to its citizens, but they wished to control the traffic of spice so that they might benefit from it financially (and also so that their opponents would not benefit from it).

Another example is gunrunning: the Empire wanted to control weapons availability in order to prevent criminals, and even more so, insurgents, such as the Rebel Alliance, from being well-armed.