I think it's because Facebook is run by those who would describe themselves as liberals--which really means that they know better than everyone else and don't have to explain anything to anyone.
Now, I fully recognize the fact that I am using Facebook at the mercy of those who OWN Facebook and, since it's their property, they're free to do as they please. However, a quick search of political groups on Facebook finds that there are far more that could be described as "left leaning" than those with bends to the right. This leads me to believe that my group was dismantled because I was not very kind to the president or "Dr." Gates. Do dear in mind that I didn't attack Gates or the pres, didn't wish them ill and didn't write anything that wasn't either the truth, or my opinion, or a fact which I felt adequately supported my opinion...I even allowed left-wing Obama worshippers to come on their and spout off--for no reason other than it was fun shooting them down.
I think the "Facebook" team gets the Who's a Douche award for the week....