A lot of companies end up going with something similar to this, since Github Enterprise costs get a little crazy. Stash is good, but if one is looking for an even lower cost option, a lot of people recommend Gitlab now-days.
However for some, the task of self-hosting is daunting. I presume that is why some are willing to pay a lot for a hosted solution.
BTW -- It's worth noting -- BitBucket is run by Atlassian and allows unlimited free private repos. I think you must pay for teams (EDIT: Free up to 5 users, $10 per month for 10 users, etc, it's basically $1 per user per month over the initial 5 free), but just throwing that out there. It's basically their hosted Stash solution.