When rpm is run as not as root, it doesn't attempt to chown(2) any of the files
it installs.  I suspect that the origin of this behavior is to permit rpm to be
run as non-root without noisy chown failures.  But I think a better solution is
to attempt the chown and fail silently if the chown fails with EPERM.

Why: in our environment we make extensive use of RPM deployment by non-root
users.  We therefore make much use of group memberships as a substitute for the
time-honored practice of running everything as root.  We quickly learned that
one could not specify group ownership in the %files section of an RPM spec file.
 Instead, one has to do an explicit chgrp in %post, which is confusing to
newcomers and hard to audit.

Hence my suggestion.  If it meets with your approval I'm can supply either of
two patches:

  1. When non-root, don't attempt change ownership, and attempt change group
  if and only if group is one of the groups of the user running RPM.

  2. When non-root, attept change ownership and change group, but do not 
  complain on failure unless errno is something other than EPERM.

(The second approach seems cleaner to me.)  Either of these changes allows RPM
to continue behaving as it does now, namely, never complaining that it has
insufficient permission to alter the owner or group of the files it installs.

Please let me know what you think, & thanks for your consideration.