Selling services 'based on mostly other people's software' is not some crime or bad thing. Servicing cars or houses made by other people is an honorable profession. So are software services. If the thing needs servicing, then I salute those who stand ready to do the dirty work.
And I didn't say it is. Only that it's usually the only way of building a business around GPL software. This is fine for serving some people, but it has a huge blind spot for those who mainly want to write Software and try to live off of it. IMO this is the main reason why Desktop linux never took off - you just don't have enough userland software that's ready for production use in a professional environment - see desktop publishing, audio, video etc. This sort of software is not going to be written as a hobby, it needs full time professional developers and investors who can see the ROI starting at around 1M$.
