To my pleasant surprise, about 80% of my academic writing students last term chose “emailing to academic staff” as the most useful thing we covered in that course.
The surprise comes from the fact that I’ve never seen it in an academic writing book, it wasn’t on the syllabus, and I only really introduced it to give my Academic Writing 1 class an easy first couple of lessons and to stop overlapping too much with the Academic Writing 2 class. When I got that response from the Academic Writing 1 class, I rushed out a class on the topic for the last lesson with Academic Writing 2, with almost identical results.
I guess the popularity of emailing as a topic for academic students is partly because some of them are not really focused on academic writing at all and are thinking more about getting into the world of work. However, it’s also because students submitting homework and papers to be published often feel less confident about the email doing so than the thing that they have attached.