Bean-counting enterprises do all kinds of annoying shit to deal with the GitHub cost, like automatically disabling user accounts after 30 days if unused, or multiple orgs.
I suppose it’s about setting different tiers depending on the orgs. For instance a higher tier for the org with your main dev repos and deployment/CI system, and more basic tier for orgs with your translators’ and QA team’s repos, etc.
Limiting number of licenses and requiring business justification, so one part of the org can't on-board 50 users that probably never need to commit anything. I imagine at some point GH might get variable pricing like NewRelic where you pay less for a read-only user.