How can even a supermarket manager make this decision on their own, without agreement from higher up?
Easily. He/She is the manager and responsible for maintaining stock.
How can even a supermarket manager make this decision on their own, without agreement from higher up?
A phone call away.
I have yet to see supermarket staff in the UK "popping to the cash and carry" when they run out of something I wanted to buy.
Perhaps that's because no British supermarket would ever run out of such a staple product as washing up liquid for three days, never mind three weeks. And if they did, the manager would no longer be the manager.
I remember my local Asda in the UK having a power cut. A supervisor stood at each check out, did a quick count of the items and asked for an estimated amount, rather lower than the actual bill would be. When it happened at a supermarket in Warsaw, they just threw the customers out. That was last year.
How can even a supermarket manager make this decision on their own
In one simple sentence, you've summed up the problem with Eastern European public life - nobody will make a decision. Why? Fear of getting it wrong? Apathy? Idleness? Given that the Polish language has no cognate for the phrase 'community-minded', could it be something deeper?
I am probably stupid,
No. Just a victim of your culture.