Blue law/ Sunday law

FeliciašŸ‡
So in the state of Tennessee and many other states there is a law where you can't buy Alcohol on Sundays from 12 am to 12 pm. I just don't understand this law. I'm a Christian, I don't drink but I think it is a stupid law when they claim separation of church and state and then on the other side claim we aren't a nation built on God but yet we have laws that are put in place because of religion.