It's all in the way it's used -- which I believe should be never. Could be used disparagingly in a light-hearted attempt to poke fun at one's own profession. Could be used in an utterly mean-spirited manner by an asshole member.
You're in the business of making a buck, but who in business isn't? Let's just leave the "whore" term out of it. Or start saying secretary whore, teacher whore, car sales whore or editor whore. I'm sure we all have days when we feel like we're prostituting ourselves for the almighty dollar, no matter what profession we're in.