I don't understand what you mean, so what that it's "controllable"? Pipboy status gives you some advantage inside the town? Serious business? Like controlling a box? Don't make me laugh. Scenario is like that: a gang comes to Modoc, talks to TC NPC and sits in some shack without windows for 20 minutes. If enemies come, there is a battle. If not, they leave because there is no miliita to hide behind and camp on grid.
See? That's your problem. You don't understand the human factor. But let me help you with three keywords: prestige, custom and rewards. Prestige, because yeah, you're controlling a box, it's your box and your name comes up on pip boy for everybody to see. Oh, and it helps with psychological warfare and recruitment. Custom, because it is customary for big gangs to battle in the unguarded, controllable towns. Rewards, because you get stuff for controlling towns, meaning you don't have to get bored crafting, at least to a degree depending on your gang's current situation, how advanced the session is (ie. how much time has passed since the last wipe) and so on.
Now, Reno doesn't have any of the aforementioned traits, so it is open for lone PvP players, small groups and generally people who just want to get some trigger time no questions asked. Modoc has all of these traits, so it's a completely different animal. And militia... well, militia doesn't come into this equation
at all. It comes into play when tactical decisions and risk assesment are involved, but it does not determine whether or not serious gang PvP is going to take place even in a slightest degree.
Actually, the best thing that could happen to Reno right now would be adding quests with NPC-based cooldown that give low-mid tier gear like assault shotguns or assault rifles more or less for free after you spend enough time inside the city. That way people could choose between low-risk, low-reward (slowly level up, hunt some mobs) way of equipping themselves or high-risk, high-reward (stay alive inside the city long enough, maybe kill some competition).