I've been signed up for email notifcation of when my bill will be auto-payed, similar to various utilities that I also auto-pay. Typically, the utilities send the date and amount to be drafted and that make my accounting simpler. AT&T only tells me the date and then I have take many extra steps to get the amount or just wait for my bank statement. I suppose the reason is an obsession with security but if I've already opted for notifications, it seems the assumption should be that I do indeed want this information without having to dig for it.
Please include an option in my profile set-up to allow my billing amount to be included in my email notifications. My email is secure enough and I have no reason to be as paranoid as you seem to be.