You've made about 3 seperate points here:
Firstly that the belief in a creator is stupid - Theland (possibly deliberately) took that to mean religous people are stupid and provided you with examples of clever religious people.
Well sometimes clever people do believe stupid things - we're all human.
I think stupid isn't a helpful word (see below for why) but it is irrational.
Secondly you make the point that religious people with nothing else in common come together and spend time with each other. I don't see why that should be at all odd. I've been a member of a number of clubs where we had nothing else in common.
Now the case quoted about sticking together because they're "thin on the ground" is classic siege mentality.
It's the logic that drives your shopping centre preachers and the wearing of turbans etc. Part of their faith is standing up to abuse and doubters - they actually are looking for people like you to call them stupid and heap scorn on them because it strengthens their bonds to each other - experiencing a common assault.
And finally that the bible can be twisted to ones purpose - well so can the law - otherwise lawyers would be out of a job. And in both cases that doesn't mean there's no good in either of them.
Of course if you take the Bible literally and go with all the talking snakes, garden of Eden and arks stuff then it's time for a reality check.