I think that some people have an unrealistic view of God and what God does or doesn't do. I think there is often misplaced anger towards God due to this.
I dont think it's healthy to think that God shouldn't let bad things happen or should stop people doing bad things.
Bad things do happen, they need to happen. It's also unhealthy to think or expect otherwise it doesn't do anyone any favours, there will always be bad people, that's not God's fault that's people's fault.
If you believe in God, then God created life, life then takes hold and well, lives for good and for bad. If you don't believe in God then the same still applies.
It's too easy just to easy to blame God, it's also much more complex than that.
If a lovely family have three kids, two grow up to be well rounded adults, the other turns out evil, is that God's fault, the parents, societies or the evil persons fault for not striving to be a better person and seeking help and support?
Same goes with illness, there are many biological factors that can determine uour likelihood of getting ill, very complex, but it's so easy just to blame God.
I personally don't mind if people believe or not but I do mind bit if they misdirect their anger and blame God etc instead of dealing with their understable anger and frustration in a more practical way, which may actually help them cope rather than blame.