In my small (12-person) design agency we have 244 repositories and we have a custom plan with Github just to pay for it. Other than rent and hosting, it's the most expensive thing that we pay for on a monthly basis.
I'd like to just stop using Github for older projects but it's not worth the headache on the off-chance that an old client pops up and needs a five-minute change that we can't then just cap deploy.
I understand the business side of this, of course. We're paying the money, so it must be a good idea for Github. However, we do have the time and inclination to find a cheaper way of doing it, and once we do, will Github's pricing be in their best interest? I guess time will tell.