Since our visit last year, I love reading about runs like this since I can picture them so well. I wish we'd visited the mystery store. That last hill to your place is a good one!
Why can't stores be open on Sundays?
Sundays are for getting out into nature and sharing a Kvikk Lunsj with your family, not for working or shopping.
I was wondering myself what the rules were because the supermarket across the road from where I'm staying, which appears to be almost full-size, is open Sundays. In Western Australia (the last Australian state which restricts the opening of supermarkets on Sundays), the rules get circumvented (or, as Australian English would put it, "rorted") by setting up corporate structures so that each store is supposedly a separate company and so falls under the maximum number of employees limit (the rules being that only businesses with fewer than a certain number of employees can open on Sundays). I'd assumed something similar happened in Norway.
The rule here is that food stores under 100 m^2 are allowed to be open on Sundays. Mostly that means that many of the smaller stores just stay open 7 days, and are frequented by every Norwegian who forget something they needed for Sunday dinner when they swarmed the the supermarkets on Saturday. Outside of the city you sometimes find a big supermarket that has a small section, completely walled off from the rest of the store, that can be open on Sundays.
The conservative parties in Parliament want to change the rule but it enjoys popular support, even among the general public who are members of those parties. People can argue about lost revenue all they want, it seems most Norwegians enjoy having a day where most people do not work and you have to do something else aside from shop.
When I worked in Sydney (Oz) a looong time ago, most shops were closed Sundays, Saturday afternoons and every evening except Thursday. At first, we Canadians couldn't imagine how people ever got things accomplished. But then we realized that people didn't plan social gatherings on Thursday evenings and they were much more efficient and organized when they shopped because they might not get another chance. They had more time to do fun things with family and friends while much of the city was closed down. In the end, we loved it.
Even in Canada, Sunday shopping is a pretty recent development. Halifax only started allowing all stores to be open on Sunday while I was in university, so maybe 2007. My memory is one grocery store figured out the current departments as separate small stores trick, then they all started doing it, so the city gave up.
Good point - Nova Scotia held out a long time! Ontario legalized Sunday shopping in 1992.
That's fairly similar timing to the larger Australian states (and Canberra). An interesting quirk is that in the Australian Capital Territory the evening shopping night in the old days was Friday whereas in New South Wales it was Thursday, so if you were really keen you could go across the border from Canberra to Queanbeyan (about 20km away) and get a second opportunity.
As for the place I saw in Sandvika, either (a) it is blatantly ignoring the law (probably knowing full well that the money they'll make by doing so is more than the maximum fine they might get) or (b) they think 100 square metres means 100 metres x 100 metres.