Sunday opening hours pre-1995 used to be 12pm-3pm, then shut until 7pm-10.30pm. In practice, that meant some people slamming down as many as they could before staggering home for lunch and a nap (source: my parents’ pub).
Think that derived from wartime licensing laws, so yeah, that probably would be popular with kippers. At least until they realised it meant going home for a bit to face their awful empty lives (or to church lol).