These bubbles I mention represent only a portion of the cities themselves. I'm not at all referring to the whole populations and areas of many third world count

These bubbles I mention represent only a portion of the cities themselves. I'm not at all referring to the whole populations and areas of many third world countries' large cities. I'm aware of how urbanized many developing countries have become. I partly speak from personal experience here too. The city I live in has a largish core urban zone that's fairly tourist-friendly, clean and highly, fashionably modernized and cultural (but with a charming colonial aspect). Since the city in general has well over 15 million inhabitants, this "bubble" area itself contains well over a million people, easily, but it's just a small fraction of the rest of the city, which is very much what you'd call a dangerously third world place in terms of crime, corruption, administrative ineptitude and barely functional infrastructure.