[goodplay]

Same use case here (with aprox. the same amount of tabs). I'd like to add that leaving a project's tabs open also helps me easily remember where I was in implementing a specific project, especially when I need to work on another project as its dependency. It's much more convenient than keeping notes or following last changes.

The point made is that different people will use software in different and unexpected ways. Assuming that people use browsers the same way you do, or assuming that a certain scenarios are "impossible" because you personally are not likely to encounter it will harm your userbase.