My reasoning: Hosting is higher risk and higher cost than invading, and constant invasions can make recharging spells impossible, thus I shy away from it as my primary means of pvp.
And I don't like being the "bad" guy.
Bad being in quotes because of the subjective nature of the term.
The darkwraiths (as a cov) murder indescriminately, and this is not how I operate. I don't have the malicious streak in me, but I really don't want to put up with humanity farming/being trapped in a stream of invaders so I cant recharge to pvp.