There is reward for everything. When you do good, you'll be rewarded likewise when you do bad you'll be rewarded. But the rewards kind of differ.
There's an adage that says: "You will not plant Groundnut and Harvest mango". Choose the right path. Its good to be good and everyone knows that. When you do good, you will want people to see you for that good but if it is bad,you do it hidden. Even religiously been good is the key for making heaven.
When you help someone it is believed that you'll receive that favour back,it may not be to you directly but your family will surely have it like wise the other aspect.
Nobody is born evil. It is the environment that influences the character development of a person. However, it still depends on the person to maintain that character of change for the better.