The market that finds them suitable are

- Those who only browse the web (no uploading/download)
- Those who do not need to perform any processor hunger tasks (e.g. photo/video editing)
- Those who need a big screen to check emails whilst traveling
- Those who need to play games/ read books on public transport on a unsuitable device

my sony Z series serves all my mobile needs. Super light and a heavy weight in power nothing comes close. Of course individual needs dictate the device.