It’s also valuable for targeting your Facebook ads. You could target people who landed on a certain page of your website (like a blog post) but didn’t opt into the content upgrade.
Here is a helpful link to explain Facebook Pixels.
http://bit.ly/How_to_Install_and_Use_the_Facebook_Pixel
There is also an extension you can install on Chrome which will allow you to see if your Pixel is working properly. This extension examines every website you visit and will report how many Pixels are being used. This is also helpful in better understanding your competitions marketing activities because not everyone is leveraging this free capability.
http://bit.ly/How_to_Install_the_Facebook_Pixel_Helper_Chrome_Extension
One last comment for the social media skeptics. Even with all the rhetoric we hear about the relevance of Facebook and it’s decline; Facebook has a huge reach into the market. Here are the latest stats as of Jan 2019.