The short answer is that because they've been indoctrinated to believe in God since they were children. Then why does belief in gods exist in the first place? It exists because humans seem to have believed in the existence of a spirit world since the dawn of the species. The human mind has a tendency to personify things and phenomena, that is, to ascribe intentions to complex phenomena that seem to have minds of their own that are seemingly impossible to explain otherwise. Think how dauntingly inexplicable in any kind of mechanistic way much of the world must have seemed to prehistoric humans. To even attempt a mechanistic explanation based on cause and effect required a leap in philosophical thought. People believe in gods because that is the default position that arises from the how the human mind works.
People believe in God because it is engraved in them, more like indoctrinated right from the time they are born. They learn they they always have to go to church, or the temple as you'll have it. It's all they've seen a they've been programmed right from the onset to always think about the creator as he controls their lives.
Another reason I because of the fear of the unknown. People fear what may happen to them, they fear what would become of them if left to their own thinking and cravings. They therefore seek solace in conjuring something or someone for themselves as their god.
People also have sometimes take a religious part because they want to take responsibility. They give all the control to their god and say he's responsible for all that happens to them and they with them.
People sometimes resort to their concept of god when they think about death. Many are afraid that things could just end for them and so seek solace in the knowledge that there's an after-life, a place where they continue living.
These are some of the reasons why people would prefer a concept of god over atheism.
I hope you've been sufficiently enlightened. Thanks for the question. It was a joy to answer.
People believe in God because of many reasons which include but not limited to indoctrination, Religion and their personal experiences. I am a believer in God and i fall in the category of the experiences i have had in my life that made me believe in God. As a kid, i was raised in Christian family and so grew up into believing in God through my parents' teaching and the teachings i received in church but all that was just religion because i had not yet encountered God at a personal level.
I was religious like most out there but after i went to the university and really had an encounter with God at a personal level, that was the moment my belief in God was more than just what i was told but what i understood from the encounter with him. That is when i realized i was not a believer in God but a follower of religion.
To put it simply, on a personal level; i don't believe in God because i have been indoctrinated or religiously dictated to or because others do but my life and where i was and who i am right now only makes me believe that God is real and exists. I believe in him because he has proven to me that he exists and not because someone told me to.
Hope this answers your question..