That's a very good translation of the word "φραπεδούπολη" indeed!
However, though I have not lived in Thessaloniki and have not grown to love it, I must note in its favor that it is also a very big university-city with a very large campus with tenths of thousand of students. They never let the coffee shops or the city center to look empty. Also there is a vast and hard-working working class, alas with high rates of unemployment. Combine these with the generally good Greek weather and our love for socialization and you have a very good part-explanation why the city-center is always full of people doing nothing special. An other part of the explanation is unfortunately as
@Ichos has described it but it is rather not special in Thessaloniki or Greece. It is our depressing modern world of "social" media, emptiness, fast money/fame and eventually a despise for real education...
