Is sufism a mild or a wild form of Islam?

Sometime back I attended a wedding of the son of a cousin in Colombo, Sri Lanka. The cousin had become a Sufi and he took us to one of his Sufi gatherings where they were jumping about like madmen and shouting "Allah O Akbar" (God is great), presided over by a visiting sheik from somewhere. I found it hilarious. To get some idea of what I saw I give you the video below. The music here has obviously been superimposed on the chanting but who knows, these screwballs might actually have had it on, mosque or no mosque.

To those of you who know a little about Islam it might appear as though these fellows are making a mockery of their religion. If Allah existed what do you think he would say to all this? I think his response would go something like this:

"Look here, you fools, there is no need to tell me that I am great. I know I am! Flattering me as if I were a child will not get you into heaven. It will get you into the other place."

My apologies to the cousin.