Ashenvale doesn't have many alliance, or at least I haven't seem more than a couple 30s so there's really no point to us camping there. Unless of course many of you are getting ganked there and I'm just not aware.
TM and Hammerfel have a slew of quests, some of which take you into camps of mobs that are nuetral to Alliance. So the alliance like to camp the area in zergs waiting for Horde players to come along on their quests.