You can tell it to do that, yes. You can also set it to forward them to rsyslog without storing anything. Or both. Read http://man7.org/linux/man-pages/man5/journald.conf.5.html and be enlightened. ;-)
OK, it's good they've added "none" option at least... It wasn't there in the initial journal design document.
So, if the storage is disabled, journalctl, systemctl status and other systemd parts that query journal just see an empty result? I.e. everything looks like you just run syslog, only messages sent from systemd get to it through journal, not directly?
Do some messages get lost in that case, for examples the ones logged before rsyslog is started? Or are they forwarded to kernel log buffer?
-- With best regards, Vitaliy Filippov