Playing games does not write at all (maybe swap, but that's an indicator of an under-RAM system more than a drive problem).
Only if you're playing shit social games.
Every single game ever saves something to disk. Especially the newer "Call of Halo" genre games that insist in autosaving after every action.
And high HDD/SSD write amounts are credible. My monthly disk write stats may be near the 1TB mark if you were to base 'em on my current uptime (6 hours, 7.51 GB written). I got to agree with Trevor_Pott here, especially as my coworker has already killed an SSD, it lasted him ~14 months.