Rich,
The problem arises when you are checking your email via your cell phone (or Blackberry in Jamie's case). It's not practical, and sometimes impossible to view the web site with these devices. It was very handy to see the text of the message in the email. In the cases where you are responding to ads, it allowed you to know whether or not you needed to get to a computer or not.
Some ad responses require immediate attention - others, do not.
I am a member on several Vbulletin boards and none of them appear to have this problem. Maybe the idiot factor is higher here. I don't know. If you like, I'll be happy to inquire on some of these other boards to determine if there is some work-around for this problem, or if they are simply tolerating it.
Thanks,