I'm sure for a set of people this is the main setup (this is totally viable, and probably opens the door to development on many alternative OSes, like on an iPad or android tablet), but I see it used a lot for "hit and run" changes on repository that are only auxiliary or seldom used.

For instance changing configuration files on a infra oriented repo, tweaking SQL on an ETL service, updating a internal library etc.

If those changes can be done in a quick and compact way, with the CI dealing with running the test, staging and release process, an online editor is the fastest approach.