I agree that the reality of the situation is that individual NCEA for small arms isn't that much of a cost. But that's not the reality that a unit lives in. Instead, they have to justify (and often beg) for additional NCEA from their ISIC just to meet the required quals, never mind also letting additional people qual. Some units will have more NCEA of a particular ordnance than others, and I agree it's dumb the way the game is played, but that doesn't change the fact that often the actual budget for small arms is hard to come by for A LOT of units, AC or RC.
All that said, if you happen to find a unit that will let you shoot, then by all means. Just don't take it personally when they say they can't afford to let extras sign up.