A cheap surface would be a pretty killer device for anyone doing their undergrad/grad studies now. In my experience, jotting down on a surface is pretty close to having a stack of A4s and a nice pen to have, you can doodle on it, organize notes, draw diagrams of varying complexity, and take notes in your own handwriting (or if it is bad, type it out).
In my experience, those in universes with math(-heavy) lectures.
And in general, scribbling notes or highlighting in provided materials isn't that unusual either, especially among those that own devices with pen input.