Interesting Quirk
When I created my AMI last night I had an EBS mounted at /data. I figured this was the way to do it, so that when I rehydrated later the mount would already be in place.
Today I rehydrated, tweaked some Postgres directory permissions and everything was good to go. I went to unmount /data so that I could terminate the VM and ran up against a wall. /data was not a mount point.
I went and mounted /dev/sdf and created a file and then checked /data. The file was not there.
Conclusion
Creating an image with mounts attached results in the data being a part of the AMI. So always remove EBS mounts unless you want the data to get included.
