Chances are you have an extension/plugin to block social media scripts or the like. They're missing on my Chrome browser (Privacy Badger, Ghostery, Disconnect, HTTPS Everywhere, etc) but the vanilla Safari (no plugins) shows them fine.
This is correct. I uploaded the images and used names like facebook.png, which sometimes produces false positives on those extensions. I can confirm they're being served from eff.org and are not doing any tracking.
