Dublin has a big problem with 3rd spaces; no cafe is open for anywhere close to that, and we are all basically shoved to pubs..
I used to sit at cafes pretty late with a laptop — buying multiple ( >= 2 ) cups of coffee, often salads and sandwiches — in the countries I lived in, but there’s none of that in Ireland. Most non-chain cafes are not open past 17; and chains go on until 20.
British culture in general is pretty bad in this regard. Even in Central London, I find Leicester Square to be the only place that's a little alive at later hours. The pub culture, which I also like, might be to blame. If you start drinking at five on a work day it's pretty easy to call an early night. (there a lot of great third places if you stick to regular early hours, like the cafes of many of the museums.)
Germany I find even worse though. It's kind of ironic since they seem to have a more robust nightclubbing culture compared to the Brits.
It's certainly normal in the Middle East where coffee is a big part of the culture. In some countries, coffee kind of fills the gap where alcohol might normally where it's banned.
They may or may not be drinking coffee - but those places don't track if people are constantly buying something. They are generally young generation, doing maybe university work, chatting up etc. I guess it works well for the coffee shop as well, as more crowded they look, more people come in.
I for one haven't been to a Starbucks anywhere in the world that even tracks whether sitting customers have ordered anything. Is this a thing? Has anyone been to such a Starbucks?