In our previous LMS (Sakai), each class was given a unique email address. A restricted set of users (instructors and TAs, I believe) had the ability to send an email to the entire class from our external email system (we use Exchange.)
Instructors are constantly receiving emails that we should "distribute to our students," yet I bet about 98% of those emails lay dormant in the instructor's work inbox. For example, many messages have attachments (PDFs) to distribute to students. To get those to my students in Canvas I have to download the attachment, start a new Canvas message, compose or paste in some information about the attachment, upload the attachment to the new message, and send.
It doesn't sound too arduous, but most people don't do it. And, if I have multiple classes (I have 6 for this Fall alone), I'd have to repeat that process 6 times.
TL;DR, the transition from our "work" inbox to our "Canvas" inbox is a huge communication fail.
If there was an easy way for me to forward these often-important messages to all of my students using the email tool where I spend 80% of my professional life, it would seriously improve our communication and save a huge amount of time for the eager beavers who do try to disseminate information the only way we currently can.