These laws make it fairer for small businesses. Large corporations can more easily stay open seven days a week and twenty-four hours a day, or for longer hours. Small business cannot possibly compete with that. These laws even things up a little.
This is a great question and one that I lived through, since I grew up in Bergen County. At times, of course, these blue laws could be annoying, but generally speaking I think these laws are a good idea. There are three reasons for this. First, it is good for people to rest. So, if stores are "forced" to be closed, then people can get some rest. Americans are some of the most overworked people in the world. Moreover, without rest, you will not be able to function well. Second, time off from work allows you to do other important things, like spend time with friends and family. Sometimes you need to be "forced" to see the beauty and importance of community. Third, look at the economic mess we are in! Because we live in a consumeristic society, we are almost programed to shop. In a word, people shop too much and save too little. Just look at all the malls in Bergen country; it is absurd. If we can challenge this consumeristic society, this is good.