I watched "My Big Fat Greek Wedding" again last weekend. I assumed it was all a joke, but maybe it presents things as they are. If so, it's just a case of nostalgia for past glory and a need to still have something to be proud of.
BTW, I don't run into any Greeks on a regular basis. For that matter, I don't run into any on an irregular basis. Last Greek I met was 2nd generation and that was 30 years ago.