Oracle would've charged per core and per GB of ram and number of containers to license your docker install. Free would allow 3 containers, on single core and 512MB ram. Sales people would be calling everyday to upgrade to docker pro, which is $120 per month/per user that will allow you to self host your registry, on premises or Managed Oracle cloud (vms and bandwidth extra). Ran docker run without a valid license? Prepare to be sued.