Isn't this really a prime example of why ROM use is illegal? While many game copyrights may not get enforced heavily, rest assured someone still owns the things. They don't really expire anymore (not anytime before most of us will be very old, if not deceased anyway, and thats if they aren't renewed.
I know it won't work, but I wouldn't blame developers who are in on the Revo thing if they started to enforce the old copyrights much more strongly, even against people who don't distribute the things.
The reality is that this is just prrof that gamers have been lying to themselves regarding the ethics of ROM use.