Goblins in Faerun = eat people like Brian. Evil, malicious monsters. Fun for adventurers to kill without feeling guilty. Same is true with gnolls.
Goblins in Eberron = neutral race that coexist with others. Not necessarily fun for adventurers to kill because you might have killed someone not necessarily bad. Now, you have to wonder. Did I just kill this goblin because he made enemies of the guy who hired me? What if he was a good guy who was working down at the refugee center helping war-torn victims of the Mourning?
If they make every race not evil and "realistic" with some good and some bad, it ruins the fun. Let me kill baddies without worrying about real life politics and social issues.
