Unfortunately this isn't a huge shock to me. Back in the 90's I remember trying to hook up a fortune 500 company to the internet. They were using public IPs on their internal network.. They complained when I told them they had to readdress their network.. I even dug up the various RFCs, who owned the public blocks they were using, etc.
There was actually a discussion along the lines of will we ever need to communicate with those companies? i.e. can we just ignore the problem.. In the end the argument that those places using public IPs wouldn't be able to communicate properly with the reset of the network got things going in the right direction..