I'm having the same issue. Almost every page it will pop up for me.
The worst is sometimes it seems to get caught in a loop and I can't get to the page. It'll give the message, I'll click the thing to confirm I'm human and try to move on....then I'm sent right back to the page again and then again...etc. Also like the OP, the IP address keeps changing, but I am not using a VPN.
I'm also using Chrome with that same extension.