Is there ever a reason to roleplay?

In this video, Blufor searches for and destroys ammo caches in a city occupied by a combination of armed and unarmed civilians. Blufor is bound by an ROE that makes the mission harder for them should they break it (e.g., if they unlawfully kill an unarmed player, the mission spawns armed AI for them to deal with).

If the civilians wanted to, they could take weapons and explosives from the ammo caches and perform hit and run attacks (and most do), but Blufor also has the ability to check if a suspected combatant has fired a weapon with their limited number of gunshot residue kits. Blufor also has a helicopter circling overhead with magnified and thermal optics, which could make fleeing difficult. I am, of course, choosing to play as a non-combatant in this video (well for most of it [spoilers]).

It's almost worth it to watch the entire 22 minutes of the video.

A long time ago I was in a roleplaying guild that hopped between a bunch of MMOs. We were in Mourning for a while, we were in WoW, we were in Shadowbane before it closed down for good, we discussed going on to a UO private server but ended up disbanding. We were never that hardcore, mostly we used RP as an excuse to write lore, and picked classes in whichever game we played that allowed us to rob, steal, kill indiscriminately. Not very exciting, and certainly a far cry from the RP that Shack Tactical (the people in that video) engage in, with a strict hierarchy, radio protocol, binding Rules of Engagement, and weapon/vehicle certifications (only some people can operate helicopters, for instance).

There was one game we did RP pretty hardcore in though. It was a browser-based mainly text-driven mmo with maybe 100 people playing (pretty exciting huh?) whose name I've forgotten. The conceit of the game was that everyone was the leader of a militia company in the middle ages, and people would band their companies together, hire themselves out, fit themselves into intricate webs of vassalage and so on. All of the actual gameplay was fairly simple (move company, recruit new men, pay men, besiege, fight) but because you were playing against humans and not going on awful PvE grinds all day most of what you actually did in the game was write short messages to people, in-character, asking for their help, forming an alliance, and so forth. There was no real mechanical enforcement of things like vassalage, it all fit together, like a good pen and paper game, on the mutual agreement of everyone playing to not fuck it up. It was cool.

So, whats the deal with roleplaying? Is it completely fine or is it categorically pathetic? I'm playing Tribes: Ascend right now and one thing I've seen people do is pick a spot on the map (the tall towers on Raindance, maybe) and play 'king of the hill' with each other and ignore the rest of the game going on around them. They also seem to like yelling at each other in some kind of half-baby half-orc patois. It's kind of annoying but it does prevent people with rocket launchers from using the towers as a vantage point. So overall it's a wash. And certainly other people in the game are RP-ing in the sense that they're ignoring the ostensible purpose of the game and playing according to their own rules. Technicians in T:A frequently roleplay as if they were TF2 engineers, a lot of other people (in capture-the-flag mode) pretend as if there were no flags and the only purpose of the game was to rack up kills. A frequent boast from the people at the top of the losing team at the end of a round is "54 kills, suck on it," as if to say "you won, but we played with style" like there isn't any intrinsic style to beasting to begin with, and that 'counting coup' with flags requires less finesse than blowing everyone away with guns designed especially for that purpose. If you can't already tell from the fact that I hold my nose high in the air and sip champagne, I play pathfinder.

I guess the difference between roleplaying and not-playing is that one is done consciously and the other isn't. But the effect, and the definition, are frequently similar: playing by your own rules to enrich an experience created, by definition, with other rules. Techs playing like they're supposed to would obviously have less fun, and if my friends and I had played that unnamed browser-based militia MMO as if it were just a system to be mastered and glitched into oblivion we would have ruined everyone else's fun as well as our own.

Playing king-of-the-hill or as if you were playing a different team-based shooter obviously pits two sets of rules against each other, but what if the two rules (the RP rules, and the actual game rules) are complementary? If they are, you get the browser MMO I was talking about, or the video at the top of the post. You get a game plus roleplaying, not a game minus roleplaying. More gameplays, more cools, additional utils of fun, beasting piled on top of beasting.

Update Sept 09 2013: I finally remembered the name of the game I was talking about in this post: it was called BattleMaster. How time flies.