Got the logic around the wrong way

src/theme/index.hbs

@@ -145,7 +145,7 @@
 
             // make sure we don't activate google analytics if the developer is 
             // inspecting the book locally...
-            if (localAddrs.indexOf(document.location.hostname) !== -1) {
+            if (localAddrs.indexOf(document.location.hostname) === -1) {
                 (function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){ (i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
                 m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
                 })(window,document,'script','https://www.google-analytics.com/analytics.js','ga');