yum-rhn-plugin on RHEL7 does not respect the keepcache=0 entry at /etc/yum.conf

Issue

• A Red Hat Enterprise Linux 7 system registered to Satellite 5.x does not respect the option keepcache=0 set at /etc/yum.conf. For any yum operation, all the RPM packages are being kept under /var/cache/yum directory.

  # cat /etc/yum.conf  | grep -v ^$ | grep -v ^#
  [main]
  cachedir=/var/cache/yum/$basearch/$releasever
  keepcache=0
  debuglevel=2
  logfile=/var/log/yum.log
  exactarch=1
  obsoletes=1
  gpgcheck=1
  plugins=1
  installonly_limit=3
  
  # yum install tree -y
  Loaded plugins: product-id, rhnplugin, search-disabled-repos, subscription-manager, verify
  This system is receiving updates from RHN Classic or Red Hat Satellite.
  Resolving Dependencies
  --> Running transaction check
  ---> Package tree.x86_64 0:1.6.0-10.el7 will be installed
  --> Finished Dependency Resolution
  
  Dependencies Resolved
  
  ===============================================================================================================
  Package             Arch                  Version                      Repository                           Size
  ===============================================================================================================
  Installing:
  tree                x86_64                1.6.0-10.el7                 rhel-x86_64-server-7                 46 k
  
  Transaction Summary
  ===============================================================================================================
  Install  1 Package
  
  Total download size: 46 k
  Installed size: 87 k
  Downloading packages:
  tree-1.6.0-10.el7.x86_64.rpm                                                               |  46 kB  00:00:00     
  Running transaction check
  Running transaction test
  Transaction test succeeded
  Running transaction
   Installing : tree-1.6.0-10.el7.x86_64                                                                       1/1 
   Verifying  : tree-1.6.0-10.el7.x86_64                                                                       1/1 
  
  Installed:
   tree.x86_64 0:1.6.0-10.el7              
  
  # tree /var/cache/yum/
  /var/cache/yum/
  └── x86_64
     └── 7Server
         ├── rhel-x86_64-server-7
         │   ├── cachecookie
         │   ├── comps.xml
         │   ├── gen
         │   │   ├── primary.xml
         │   │   └── primary.xml.sqlite
         │   ├── packages
         │   │   └── tree-1.6.0-10.el7.x86_64.rpm
         │   ├── primary.xml.gz
         │   ├── repomd.xml
         │   ├── rhnversion
         │   └── updateinfo.xml.gz
         └── rhnplugin.repos
  
  5 directories, 10 files