Birthright

[OrlockDelesian]

Hi! I've been reading the 3.5 conversion of the Birthright campaign, and I wanted to ask something I do not understand of the world.
Why would anyone in their sound minds would enter the shadow world?
I've read both the 2nd edition sourcebook and the 3rd edition one but I cannot find any benefits.
Is anyone in the playground able to enlighten me?

[Alleran]

Rapid transport from place to place, and it also provides a jumping point to reach the rest of the Planes (provided that you can get out of the "muck" that it's described as).

[avr]

Chasing an enemy holding the MacGuffin
Losing an enemy who can't or won't follow you there
Exploration: because it's there!
Bypassing enemy armies
Loot
Altruism: save the benighted inhabitants from their fate
Territory you can rule without having a bloodline (better to reign in hell than serve in heaven)