[@Animus] 

Don't overestimate the budget of a 'local gang' - it's highly unlikely that they could afford an Arms Master that could do what you're describing. It's far more likely that they would have low-end Arms Masters of their own. Also, there's law enforcement to consider. If some local gang of ruffians have Arms Masters, then what would the police have? 

In the end, most Arms Masters that have Noble Arms that are worthy of note (i.e, destructive, capable of mass destruction) would rather avoid using their powers so conspicuously.