To rephrase
MC&D isnt just a vendor job, its much more, its a job that allows you to rp as a multitude of things because you can choose how to play it.
You can choose to be a bartender with "legal" firearm sales quietly in the back, you can choose not to sell any firearms at all instead making money through the sales of drugs, drinks or anomalies, you can choose to close up for a bit and RP with anyone on the surface.
MC&D isnt necessarily a vendor, its kind of intended as a vendor but that doesnt mean you cant RP in other ways.
Better?