The episode count wasn't where they abandoned the series for shinier, more lucrative opportunities. That was the DVD.
It's obvious from the rushed, haphazard nature of the W&G DVD that it didn't perform as well as they hoped. Even during the series' own damn run, the upcoming Tales usurped its place obscenely fast. Bogey Man was only front page material for a day.
It's a shame, too. The games themselves are GREAT, some of the best adventures Telltale has done.