Not that long ago, malls in some states, North Dakota, were closed on Sunday. Then grocery stores were open, then malls in the afternoon and so on. Sales of alcohol were strictly limited also, none on Sunday until relatively recently. Then, alcohol was allowed only after Noon on Sunday.
While some of these “Blue Laws” were supported by businesses which did not want to staff more hours a week, the real support came from the religious community. It was believed, and apparently there is some evidence for this, that malls and bars compete with churches for peoples’ time. The link laments the time when lawmakers were sensitive to the preferences of churches in such matters is gone.
I know from a former life that there sometimes are good reasons for limiting hours businesses are open. Bars at night, for example, have more police calls than other types of businesses. Laws that close bars by 2PM limit the number of police officers a city needs to hire. Bars open in the mornings, like Sunday morning, don’t have problems and this is not a reason to keep them closed.
I don’t know of a reason, other than competition with church, retail stores cannot be open whatever hours they choose. In towns/cities with lots of tourists retail stores are open early Sunday morning. I remember being in Wall, SD back when stores were mostly closed on Sunday. Little Wall, however, knew people could find some other time for church.