Thanks kinggo, I missed this bit:

There is a huge difference between sharing a camera and sharing accounts. A camera is a hardware resource and as such it has to be shared. There is just no way around it. You could just as well argue that all applications should share accounts because they all share the same screen, speaker, RAM and CPU.

Accounts are a soft resource. Not just software but soft. That means, you can have as many of them as you want. There is no technical need to share them. In fact you can find gazillions of requests on TJC to separate accounts for Phone and WhatsIt, or whatever it is called.