Why is the system/core-os IPS package dependent on the media/cdrtools package

I'm attempting to minimize the necessary packages on my system, and I'm curious why the cdrtools package is a requirement for core-os functionalty? I'm aware that I can modify the dependencies within the core-os package manifest, but I'd prefer not to go that route. I'm also curious why the install/distribution-constructor package is required even when the overall package group is solaris-minimal-server. I would not think these packages would be required in a minimal server configuration.