The last few places that I worked at only had one big repository hosting all of the projects. They weren't using Git though, SVN and Perforce.
In some ways I can see the ability to have fewer users and more repositories suited towards consultancies (specifically web development). Where there are a lot of projects and customers.
Yeah, I worked at a company that used one big repository for all their software. It wasn't to save money (they were spending quite a lot of money on other tools), but it was just more comfortable for them - in terms of code management, deployment etc. But still, with the old Github pricing, they were paying just a few bucks for a team of 10 people, so in this case getting paid per user makes much more sense.
