Andrew Morris writes in his article In good faith about the normal side of Islam, the peaceful side practised by almost all Muslims almost all of the time. He also talks in quite general terms about what motivates people to practise a religion, mentioning that belief in the existence of god is for the most part quite irrelevant.
The media is obsessed with those who preach and proclaim the `truth` of Islam, and concentrates on the outlandish personalities, the orthodoxies, the narrow interpretations, the perceived `mediaevalism` and `inflexibility` of the faith. But all that is a long way from people`s experience here, as they go about their daily lives, looking out for each other, complaining about the government, dodging cars, getting food on the table and kids into school. They care as much for dogma as your average Saturday shopper back home worries about the meaning of the Trinity.
In fact the question of whether religions are true seems almost irrelevant in this context. People observe religions not just because they represent `revealed truth` (an abstract concept for most), but because for them religion seems to work, just as it worked for their forefathers.