I don't really get why you'd waste space on a battery in a device like this. It's going to be used plugged in, so who needs it? I know there's the idea of AR go

I don't really get why you'd waste space on a battery in a device like this. It's going to be used plugged in, so who needs it? I know there's the idea of AR goggles but like, c'mon. Nobody really believes that will be more common than plugging it into a screen do they?