It's surprising that one of the groups lobbying for mandatory closed Sundays in Ga. is the Liquor Retailers. Their reasoning is that there is a finite demand and that demand will buy the same amount in six days as it would in seven. Being open a seventh day wouldn't generate any more revenue but would require them to pay the help an extra day. Less profit.
Thinking about it, the people most effected are the travelers and visitors who are surprised by the closed Sunday rule. The locals who drink plan on it and it isn't much of an inconvenience.