There is a psychological basis for your fundamentalist neighbors' behavior
They are utterly dependent on others for their survival. They rely on other people predictably following religious customs. It makes them feel secure, and in some cases give them an advantage in life. A person who does not follow the same guidelines is unpredictable to them, might not support their needs, and therefore might threaten their ability to survive. Their fear of unreligious people, even agnostic people, is evidence that they are maladjusted to the world, and very sensitive to cultural changes. That is their problem, not yours.