Hi f2n, thank you for raising this concern. is_tor and is_anonymous are true for any and all nodes on the Tor network. I'd love to hear more about your concerns, please send me an email at jonathan at ipdata dot co
A few years ago I ran a no-exit relay from home. Eventually Hulu blocked my IP, even though all traffic from my IP to hulu was from me, and not via tor. Hulu couldn't be bothered to differentiate, and just assumed that a tor node at my IP address meant that traffic coming from that IP must be something routed via Tor.
By not differentiating, you are making the same mistake, and will punish people for no reason.
Edit: Assuming you are pulling the 'exit node list' you link below, I don't see how that is happening, as it does at least claim to verify that you can actually exit through the node.