If a person told you about the IDs and you then used this resulting info, is it insider trading?
I wonder how many degrees away from the base info you have to be for it to be an issue
It still has the integer ID in the URL, so if you're willing to drop $20 a week on getting your own pizza, you can still see how many online orders Dominoes gets - it could be valuable information for competitors, or investors, as you say.