Yes, it is hard.
This is why I think that is so:
If you would prefer a religious person to believe in just existence, the burden would rest upon you to prove there was no God. This would be very hard to do with a religious person. However, if a religious person wanted an aspiritual person to believe in God, all he or she would have to do is get the person to believe that just one event in their life was influenced by a divine presence. This, I think, is much easier to do than the former. That's one reason why I think it's hard for people to believe the world just ends.
I guess the reasoning behind that is that many people grew up with their faith. They were surrounding by loving and emphatic people who believed what they were saying. God became interweaved into their world view. And to rearrange that, I imagine, would be the equivalent of changing the view of a flat world to a view of the world as round.
I myself keep my belief in God, and other of my spiritual beliefs (like a spirit world), because they work for me. They make me a better person, and they help give me strength. And in the end, if I'm plumb wrong, what does it matter? I was a good person and felt I had extra strength? Horror!
But I think the fact that it works is important. If I took that away, I might actually have to work harder. So maybe I'm just lazy?