First, the ones who have experienced the harsh Wahab reign of ISIL have likely lost a lot of faith in Islam. Second, they are in a new country and have seen enough in the old one that they never want to return, so they're adopting all the trappings of that new country as fast as they can. This phenomenon was also seen in the Irish fleeing the potato famine.

I know a few Muslims in this country who converted, mostly because it was easier on their kids. They still suppress a shudder when they look at the pork in the supermarket.