Games work best when there's a conflict to overcome. Whilst modern titles like Call of Duty can simulate realistic warzones, games were built off the back of imaginative - often overpowering - threats, often in the guise of a domineering alien force. Seen as far back as games like as Space Invaders, Asteroids, Galaga etc. this inhuman threat bypassed concern and oppositions that many parents might have had with their children revelling in the act of killing humans. It's an archetype that has been revisited countess times, year in, year out. From the aforementioned titles, into games like Metroid and Alien Storm, through bigger games like Halo and Gears of War and all the way to today's Destiny or XCOM, aliens have waged wars, made allegiances and been reimagined to reflect every possible portion of real-world society. Players have fought and defended endless races, and as gaming continues, you can almost guarantee the aliens will be there too.
