I think one of the reasons that people use email instead of calling is because they do not feel like talking to a machine or having to press 8 number sequences to reach alive breathing human being. I know I have tried calling some companies and was greeted with the jump through hoops machine. But when I emailed these companies in the morning usually next day or that afternoon my emails are answered. Also this gives me a written record of what they said so there is a sense of security knowing they will probably not lie to me because I can always throw the email back at them. Just my 2 cents.