Earlier quoted context omitted.
If you consider $7 (or $12) a month a lot of money for software then you're probably not in the target audience for any (SaaS) software product. A lot of people are willing to pay some money for a SaaS product even when there are free alternatives. I can't think of any piece of software I use regularly that doesn't cross the "worth at least $7 bucks" boundary.
But it's not just $7. We are a small consulting company, with a lot of git repositories. Our total costs would be more in the range of $50 a month. That's what I am getting at. $7 a month is not all that expensive, you're right - but I am only getting 5 private repositories for that $7 a month. It just doesn't make sense to use github for private work when you have a lot of repositories.
In fact, you are putting more burden on yourself for little value. It takes 15 minutes to walk the client through how to pay for and manage a github organization. I do it with all of my clients. It is an opportunity to teach/coach and give them a sense of ownership which is how it should be.