I see hospitaller and Kutt spamming NA1 looking for mercs to field a roster. Sometimes I will sign up for them in these battles because I like to see equal sided fights, and they don't even bother to sign me up. Just to clarify, I am always around level 27-31, my performance is between 7-9, and I never request any gold.
Also, unless I have a reason to not sign up for a clan/a friend is leading the battle, I will sign up for both sides in the morning and it is never the Hospitaller/Kutt side that accepts me.