freitasm: If you don't have those then you still have to buy. I am thinking from the perspective of someone who has nothing and want to start. The return may not be enough if you have to buy something. But if you invest in four or five of those and run of a USB Hub like the one you linked before then scale kicks in and it starts being a good proposition.
Your initial objection was badly founded and there's no point trying to defend it. The population on GZ isn't typical and while not everyone would have SOME USB equipped 24*7 device, MANY people on here would.
Personally I have 6.
If this was knittersweekly.co.nz then your objection may make a bit more sense.
Cheers - N