You know what? It's great to work with someone who is willing to help make your writing the best it can be. You may not receive payment for the piece when it is published, but you gain the wisdom and experience to go on to your next piece and get it right. You still get the publishing credit even though you don't receive money. But sometimes the experience is much more valuable than what you would get paid. I guess what I'm trying to say is, if you have the opportunity to publish without payment, try it, you may be pleasantly surprised by the benefits.