Well for stores of this style yeah, probably before like the 1890s or so. The store owner probably lived as part of the store, opened at sunrise, closed when it died down, but would come down for you and open up if you knocked real hard.

But like public markets have always had pretty strict hours, often historically around church. Church is out, bell rings, market is open, ring another bell, market is closed. And a lot of that was actually in place to prevent people from getting in earlier, buying up everything, and then selling it at a premium. It was like the anti-scalper for medieval markets lol.

The other half of that though is that while capitalism brought about more strict timekeeping you're right, though ironically the strict hours allow for things like https://en.wikipedia.org/wiki/Early_Closing_Association that morphed into more and more labor protection we see today

thing is, they just distilled it down to having a sign that says if it's open or closed, and made no effort to inform people when they can expect it to be open.

Most things are probably open at 14:00, that's yer lot

Or sometimes none at all

flexible closing hours is fairly normal for food places i think, though usually "closes 20:00, but we might stay open until activity dies down"