From a different perspective. I maintain a Web site for an actor. Originally, I did have an email address posted, and then later a form (the form was initially to keep the spammers from harvesting the emails), and now there's no email address. When I had the email address, everyone under the sun emailed me. Some thought they were getting the actor himself and even gave out personal information, even though the address said "Web master." Some asked incredibly dumb questions or wanted me to send them ten autographed photos. When I went to the form, it oddly enough, cut back a lot of this. I guess it was easier to dash off an email than to fill out the form. I eventually took even it down because the fans were really getting kind of nutty.
On my own site, I actually ended up pulling down some content because it was generating really stupid questions through email. For a while, I'd had some Word tips for writers up, as well as a guide to army military ranks. The Word tips came down after people started routinely emailing me asking me how to do something in Word--and it was something they could have found on their own if they looked a little more. If I helped, I invariably got more questions. The military ranks came down after I got multiple questions about them, including one woman wanting to know where to get replacements of her husband's award certificates. I actually answered that one by giving her the link to the DOD Web site, and she responded back rather nastily that wasn't what she was looking for and asked for exactly the same thing. And we rountinely get emails asking us to tell the sender how much their Civil War firearm is worth.
So, if the author doesn't have the email address up, it could be spammers, but it also could be that people were starting to hit the annoyance factor.