My point is that most people wanting a smaller (2nd) device will be using it outside the house or office. So you don't have access to a power source.
Yes, you can look at it that way but it's still $25 for a product which is pretty much useless as soon as the battery has died.Way too expensive is subjective really. It is a variable voltage and variable wattage device, so think of it as an eGo on steroids.
I'd rather pay $10 more for a similar product with replaceable battery.