Why is dpkg.log root-only?

[Daniel Burrows <dburrows@debian.org>]

  As you might know, I'm looking into improving aptitude's facilities
for tracking and displaying the history of what's been done with a
package.  Obviously, part of this is the dpkg history of the package,
so I thought maybe I could parse dpkg.log to extract that information.
But aptitude is often run as a non-root user, and I noticed this:

daniel@emurlahn:~$ less /var/log/dpkg.log
/var/log/dpkg.log: Permission denied

  I was wondering, is there a specific security reason that this
information is hidden from non-root users?  If there is, I should
probably consider doing the same thing in aptitude.  But it would
really suck if users couldn't pull up this very useful information
unless they were running aptitude as root.

     Thanks,
  Daniel