It was a call that we were unable to refuse. That's okay.  People always talk about the lack of freedom but it doesn't bother us.  In return for giving up our freedom, we get something that we could not achieve on our own.  A sense of family.  A sense that we belong and that we are wanted.  We're a solitary group of people and don't really understand how to bond.  This summoning is a way for us to bond in a shared goal.

Besides... he's never asked us to do anything that we weren't willing to do ourselves.  At least, that's what we believe.