Jacky we can all agree that over the top militia is bad. Nobody wants it except perhaps some extremists.
What I'm trying to say is that you won't have anyone to ambush in towns if there is no reason to be inside. People don't just hang out in dangerous locations for fun, unless it's organized pvp unit desperate for action, some carebear roleplayers or a bunch of bluesuit trolls. The presence of militia, even weak militia, encourages players to come in towns as long as they are not shot in sight.