A Facebook pixel helps to build a narrow / targeted custom audience focused on people who visited my website (this is really important).
The problem is that anyone can see my FB pixel ID on my webpage (it's in the source!).
Now what if someone wants to ruin my custom audience by using this script with my own FB pixel ID on a crappy website that has lots of visitors?
<script>!function(f,b,e,v,n,t,s){if(f.fbq)return;n=f.fbq=function(){n.callMethod?n.callMethod.apply(n,arguments):n.queue.push(arguments)};if(!f._fbq)f._fbq=n;n.push=n;n.loaded=!0;n.version='2.0';n.queue=[];t=b.createElement(e);t.async=!0;t.src=v;s=b.getElementsByTagName(e)[0];s.parentNode.insertBefore(t,s)}(window,document,'script','https://connect.facebook.net/en_US/fbevents.js');fbq('init', '<MYKEY>'); // Insert your pixel ID here.fbq('track', 'PageView');</script>Then my custom audience (using my FB pixel ID) will be "polluted" by lots of visits to the crappy website.
Then any retargeting campaign will be focused on these random visitors (who didn't visit my website but the crappy website), which would mean a low conversion rate, causing the loss of ad-spending.
Is there really no way to avoid this?
