Unfair how? Facebook gets more traffic than YouTube. Why not let the public make up their mind? Or publish two versions? Or somehow otherwise make data available about THEIR sites that they've made available about everyone elses?
Seems like a slightly pointless list otherwise... "Here are the top sites in the world!... except for the ones we've taken out."
Imagine, just for a moment, what would happen if the did release their data.
People would criticize their decision either way …
Unfair because they have the exact figures for themselves where they don't for others. It would be kind of slimy to know you have X visitors and then guess for everyone else. If you were in the same vertical as a Google service and were behind them it would seem very unfair, more so if you knew your traffic was actually higher than estimated.