This is embarassing.
My wife and I go to a local coffee house for a social hour with a meet-up Atheist group once every month or so. Sometimes we all joke about passing the hat so we can build our own clubhouse.
Likewise, sometimes our group teams up with another (there are other atheist groups in the area) at one of the local colleges to have a speaker give a lecture about something or another (the big bang, Darwin, NASA, evolutionary biology, etc.). But ultimately it's all about the social aspect.
These do-it-yourself Sunday Assembly gatherings seem rather similar: keeping the social aspect of a church while ditching God and any supernatural aspects of it.
If someone opened an atheist collective like this in my area, I'd certainly go check it out. If I enjoyed it, I'd keep going. That the people in this video seem like irreverent wise-asses gives me the sense that I'd enjoy it. That fact that religious folks hate it is just a bonus.
That is one advantage churches have, the social aspect, that we have a hard time duplicating, perhaps because it's hard to get people together on account of something they are not. (I imagine humanist groups have a better success rate; there is some focus there on what the members actually are.)
Why Sunday, that's my sleep in day!