That's the nature of BGs Well, with a slight "lorewise-favor" towards Forsaken since they are said to occupy Gilneas, the outdoor zone.
What needs resolving is how the Forsaken can be occupying Gilneas when they're attacking by sea in the BG. I suspect they loose it to the Alliance fleet, TBH.
Serve the hive
Feel the groove
I control
The way you move