Why on Earth would your refrigerator have to be online to keep track of food expiration dates? Can't you use a tablet, phone or PC to keep track of that?
Err! wouldn't it be easier to write on the packages or containers if they don't have expiration date. Or just take a tentative smell on a regular basis and throw-out the foodstuff that has gone off or has mould growing on it
What is someone breaks in, gets command line access and uses trusted commands to send the data elsewhere. The hacker used trusted programs to do the breach so white list would not stop it.
Well your machine is now compromised. You now have to ask the question "What can I do". Normally in a case like this you should do a fresh OS install from a trusted source (eg. bootable CD/DVD, USB key) followed by appropriate customisations then updates from a trusted source. You could do a recovery from your OS backup but if you have been compromised I would not trust this.
Obviously you may need to recover your user data if that has also been compromised but if are looking at an enterprise system or even just a home PC, initially you may not need to do this until all interested parties (eg. DB administrators) have checked for issues since you cannot be sure if your backups have not been compromised as well. This is why an appropriate documented disaster recovery plan needs to be in place whether the system is a multi million dollar Enterprise system system or a home computer.
Why did the Roman Empire collapse? What is the Latin for office automation?