Suddenly remembers something
There's no point in arguing realism in a GTA game, especially one as old as VC. Goodluck carrying 6 weapons including RPG around on the street and managing to hide them all 
only this isn't about realism, but about balance
we all know that smugglers can't leave the ship when 2 / 3 (or more) SWAT spam grenades (and 1 SWAT has 5 grenades) onto the yacht seconds before you get rewards / after you get them
note I said: can't leave. I am well aware of what smugglers can do to get their items out of there, but that's not a solution to the situation, not at all