Why do people create art like photographs?

They do it to express there feelings and to just have fun.

I agree with the other answer. But I'd also like to add a few reasons. It creates a greater imaginative depth to most fictional realism. And very realistic art  can be much more expressive in ways, it can say more to some people, and can be easier to relate with to some. Also, a lot of modern realism and realistic art is hard to do, and is used for showing off, or sharing ideas.

Hope I helped! :)