Many things that were outlawed made their way to the scene in the night market. These things were mostly weapons, and some were contraband items that were imported from different countries that were in enmity with New Oalta.
Verinia felt that the Sovereigns were very petty. Just because the continent was not on good terms with another country, they wanted to ban everything that came from there, including the people.
She also had her pride, obviously, but that was not how she would do things. Items were money, and even though New Oalta did not lack for things, other countries were still ingenious in their inventions and discoveries.
Because of this, there was a demand, and since the government did not import those things in broad daylight, others were forced to bring them out at night.
Of course, these items could not be displayed in the eyes of the guards, but just because the guards didn't see those things did not mean that they didn't know about them.