Hi there,
My family are not particularly religious, but my mother remembers that she was not allowed to go out and play on a Sunday at all. Both her and her brother had to sit inside and read quietly, regardless of whether they had been to church or Sunday school, or whatever. And this is only going back to the 50s/60s. The Church of Scotland could be a bit austere at times, even in the 20th century, although less so than some of the breakaway churches.
Clare