Niche item
Have a little mount adapter that attaches to my car's CD slot - hang an Asus Zenpad off it. Monitors car performance, systems, etc via BT, and does GPS mapping duties as well as running audio/video.
Or watch movies/whatever when cooking. That's it. My 2013 CF-53 Toughbook is my main machine, with a seriously overpowered dev machine sitting in the corner for heavy stuff.
If you really thinking about it, 99% mobile sites suck monkey balls and don't have the functionality of a full website, so what's the point of using a tablet?
Apologies for the rambling, but I don't think about them any longer - was fun while it lasted though.