That was partially it. The other part was the stores that were open during the prohibited times usually sold allowed items also (medicine, food, diapers, etc.)

As far as I know, the law has been repealed. Before I moved away I saw them implement Sunday beer and wine sales (still no sunday liquor sales) and do not remember having difficulty buying the previously restricted items on Sunday.

It was weird entering a Wal-Mart (or other large store) and seeing a large section of items roped off.