It isn't bizarre that rules and practice vary widely in different cultural contexts. Even your claim is caveated as "most of EU," recognizing that it might not be the same in all places.

In many places in the US, there is a culture of legibility, whereby informational affordances are relevantly and generously provisioned. This allows for more certainty for both facility users and rule enforcers. On the flip side, there are a lot of signs all over the place.