Why does cron_system_entry() lack an allow entrypoint?

Hi all, first message for the new year. Best wishes for everyone in 2019. As per title, the interface doesn't have an allow: entrypoint when it's intended to be used to transition cron to the target domain. Instead I need to manually allow it in my local policy. Specifically looking at system cron jobs: system_cronjob_t. I'm just wondering why it's not included when there's already the needed exec and type transition allow. If someone more knowledgeable can shed some light that would be appreciated. Cheers.