To a degree, even Chess is like this. Chess has a hint of a politico-strategic element to it in the names of its pieces: King, Queen, Bishop, Knight, Rook, Pawn, but the names of the pieces are only incidental to gameplay. They could be called Dog, Top Hat, Wheel Barrow, Race Car, Boot, and Iron, and it would still be the same game. But naming the game pieces after personalities (or fortifications), instills in the player the politico-strategic element to the game, and the players can better imagine it to be a battle of political heavyweights as the maneuverings of the pieces are analogues to maneuverings in a political environment.
At least until they start playing. When the game actually begins, the last thing a player is thinking about is "political machinations." They're thinking of things like the "English Opening", or the "Sicilian Defense", which describe certain opening moves. (I'm far from a chess expert--I just looked up some openings and picked two at random).
If a motivator to play the game is because it's an analogue to political maneuverings, it has been lost. The game has become divorced from its abstract background, and has fallen into a set pattern of opening moves, some of them so common that they've practically become scripted. These moves have been analyzed by expert players to death.
This perspective of the game is certainly not limited to Chess. I'm also a casual Real-Time Strategy game player, and a fan of StarCraft. Soon StarCraft II will be released, but in the meantime the beta is out. I recently got into the beta and have been playing a few games (and losing--clearly I need to get rid of the rust after ten years since I last played the original StarCraft). The StarCraft universe has a rich background, involving three races (Terran, Zerg, and Protoss), each striving for dominance. The game has a single-player mode that consists of multiple missions/games/scenarios in a story-driven campaign where you learn about the conflicting motivations of the three races and how they relate to each other (usually through violence).
But then, fully drawn in by the rich story, it then comes to an end, and the player, wanting a fresh experience, is left with one major outlet to play the game--the multiplayer mode. Nowadays StarCraft is all about the multiplayer mode. What was once an add-on for many games has now become their reason for being. But the multiplayer takes the rich background that hooked the players and tosses it out the window.
The rich background of the game allows the players to imagine Terran marines using their Gauss Rifles to fend off leaping Zerglings and Hydralisks while Siege Tanks support them with deadly artillery fire, and Protoss Zealots wielding their Psionic Blades and raging over the loss of their homeplanet of Aiur to plunge into close combat for revenge.
At least until they start playing. When the game actually begins, the last thing a player is thinking about is Gauss Rifles and Psionic Blades. They're thinking of things like "Marauder Builds", "Muta-ling Builds", "Reaper Rush", splash damage, micro and macro. (the terms micromanagement and macromanagement taking too long to say for such a fast-paced game as StarCraft.) The gamer terminology has overtaken the background to such a degree that players even refer to units with special powers and/or abilities as "casting spells," despite spells usually being associated with science fantasy rather than science fiction. Races in the background story who are the most vicious of enemies, e.g. Protoss and Zerg, are now allies as often as not in the multiplayer environment.
The background as a motivator to draw interest into the game has served its purpose, which can now be ignored. The game has become divorced from its background and has fallen into a pattern of strategies, based not on the background of the game, but rather the damage models used by the game, and the tactics players use to get the most out of the various units. These tactics have been analyzed by expert players to death.
Does any of this sound familiar?
Warhammer 40k is a game with an extremely rich background. Background text is all over the rulebooks, codices, etc. The art in the rulebooks inspires us to imagine the 40k Universe. Black Library publishes novel after novel of what could be argued is just "fluff" for the game (but just as arguably it exists in its own right these days).
But all of this just serves to get us to play the game. (I'd argue that the whole hobby aspect of painting miniatures is an offshoot of the origin of 40k as a game rather than the other way around, as the company is Games Workshop, not Hobbies Workshop, but that's a discussion for another day) Once the game actually starts, who among us bothers to truly think in terms of what is happening from a "background" perspective? We don't really imagine the Space Marines plowing into melee and beating on orks with their chainswords. We think about getting the +1 attack on the charge, re-rolls to wound, winning the combat resolution. We make "Leafblower" army lists, focus on our ability to kill MEQ, and are desperate about getting on troops choices the on objective markers in Turn 5. At tournaments the majority of games are marines vs. marines.
The amazing background of the 40k universe has served its purpose--to get us to play the game. It's rich enough that when we're not playing the game, we still manage to obsess about it, and so much of it would live on even if 40k the game ceased to exist. But while we are playing the game...where does it all go?