I think a lot of people are confused about Open Source. Open Source does not mean that you can't make money from it. All it means is that Code for the software is available for everybody to see, modify, and distribute for free. Look at Red Hat, Novell, IBM they are all making money from it.
Prove nothing just saying that you can make money by providing service for Open Source. Is that not why where all here?
The one thing most open source software doesn't offer is direct support from the publisher. There are a lot of companies set up to provide service and support for open source software, which fills this void.
I think it's a great service to install open-source scripts for web-design clients and then provide some basic support to them just to get them up and running. (and charge them for that, of course.) I've seen that mentioned as ok by some open source projects. I think some of them just don't like people selling their code outright.
Mozilla firefox made $56 million, with an expected 130M+ this year. People have giant sites spreading open source projects making other people rich.