If I need something on Sunday, I go to New York. So NJ loses the tax revenue and the local businesses lose out. Traffic is a part of living in a populated area, five miles from NYC. That doesn't mean we pass silly outdated laws that hurt us economically and inconvenience us personally.
Most people have only two days off. During the week it is very inconvenient with both parents working and kids at home to run essential shopping errands. The weekends are when most people can get to the mall. To take one of the two days out of the equation is utterly ridiculous and when going on Saturdays the crowds and traffic are crazy. Opening on Sunday would ease this Saturday traffic.
The cost trade off of living in a town that has a property tax amazingly low for the county and a town with an incredible amount of revenue is the traffic.