I am not going to come from this from a christians point of view as i am agnostic, what is exactly wrong though in having just one day without shops going full steam and people just take time to chill.?
Most of the larger supermarkets open 24/6 as it is,and 6 hours sunday why the rush to 24/7 they say the brits do longer hours then people on the continent and have no proper time with their families, is dragging your backside around a supermarket sunday really quality time.
I think the economy aspect is overplayed myself people can only spend their money once if they cannot shop in the time available now 24/6 and 6 hours sunday there really is no hope.