Especially head scratching given that Google's Pub/Sub has an emulator as does SNS/SQS via LocalStack.
I am also a big fan of ASB and I cannot fathom how a multi-billion dollar company that bills itself on developer productivity can't ship emulators for their cloud suite.
If even for their own internal testing and release validation.
Which is too bad, because ASB is awesome, IMO the best Azure service.