complains about missing [groups] when it shouldn't

Apache snippet is:
<Location /repos/binaries>
DAV svn
SVNPath /srv/svn/binaries
AuthzSVNCrowdAccessFile /etc/subversion/crowdauthz.binaries
Include auth_crowd.conf
Require group binaries_ro Enterprise

1. Limit write permission to list of valid users.
   <LimitExcept GET PROPFIND OPTIONS REPORT>
   Require group binaries_rw Enterprise
   </LimitExcept>
   </Location>

If /etc/subversion/crowdauthz.binaries is:
[/]
*=rw

we get an error "groups section not found", we also get it for:
[groups]

[/]
*=rw

and:
[groups]
#comment

[/]
*=rw

but not for this (dummy is not valid group AFAIK):
[groups]
dummy=

[/]
*=rw