If there is a God, then why is there religion?

[Roberta B]

Someone asked that question in a twitter (tweet), I have two valid answers, but want to hear short answers from other people.
@Best for business I have no desire to offend anyone either. I acknowledge the existence of God, and have two answers which I think are reasonable and not at all offensive. But I would like to read other answers, and will give mine in about two hours, and will give a best answer in three or four hours
Religion (or, forms of worship) exist because it is all about making choices.
1)The real God of love and wisdom would want for those who choose to love him to reveal themselves by being together, supporting one another in true love, and by recommending God's way to others. This is the clean and undefiled religion.
2)The real God would also be one of power and justice, who would allow those who choose to practice what is bad to reveal themselves by inventing the commandments of men and teaching them as doctrines. This is the religion of those who "publicly declare that they know God, but disown him by their works."
John 13:34, 35, Matthew 15:8, 9, Titus 1:16, James 1:27