Take a look at this exchange between zoologist Dr. Danielle Lee, a blogger for Scientific American, and a blog editor named "Ofek" who wanted her to provide content at Biology-Online.org:
"What are your payment rates for guest bloggers?”
"We don't pay."
“Thank you very much, but I will have to decline your offer. Have a great day."
“Because we don’t pay for blog entries? Are you an urban scientist or an urban whore?”
These kind of nasty, bullying people will always be with us and it's not news to anyone in the creative arts.
The whole story is here.
Getting Paid for Your Creative Work.
Harlan Ellison: Pay the Writer