It's a weapon, If they only have 3 shots with it what's the point of having it?
Maybe instead of being able to purchase ammo you increase the starting ammo in the rocket launcher itself
Edit: It actually doesn't make sense lore wise to carry more than a certain amount of rockets, Maybe 5? Changing to neutral
If you did a city occupation map change then the whole method of the server would need to shift from MLRP to City RP, These would be better for events.