They don't just bundle it, they make it auto-start on screen on Windows machines whether you've got an account or not.
I've got a work laptop with a teams for the work domain which I want.
There's also a completely different copy of teams, "Microsoft teams (Personal)" teams, which I have to close.
Not just every boot, even after I close it manually, I still find it running constantly.
I've no idea what triggers it, but it doesn't seem to obey any startup settings.