I guess we can assume whatever we like.
I know she was on twd's podcast and maybe she explains on there but that's not really something I really want to listen to.
Honestly, at face value it seems like Emily gets more out of it than the show does but the show is kind of hard up right now among other reasons. And some people have always thought Emily wanted her singing on the show but it's been confirmed they originally came to her after one of her concerts.