Question about religion?

Currently, I don't particularly believe in any god(s). I understand that it provides security for the unknown of what's after death, and it also presents a reasonable moral code. So why is it that whenever something good happens, people immediately jump to the conclusion that "God" did this when it was obviously something else. An example would be a team of highly skilled surgeons saving a 5 year olds' life by removing a cancerous growth from his head and the mother saying, "Thank God". Some people would say that it was through these surgeons that "God" worked his miracles. Then why didn't "God" invoke a full and speedy recovery without costing the family thousands in medical bills and hurting the boys chance on a college education?