That's an odd way to view things. It's like you don't want this topic discussed for some reason. No one should ever mention "dating in USA" then because its 50 states as well as several territories. How dare we ever speak about it! If 20 provinces is too "wide a concept" , would a country with 8 provinces be okay? Hmmm.. 5? How many socioeconomic groups allowed?
You also assume people are only dealing with dating upper middle class Argentinians in Palermo and Recoleta. I don't live in either neighborhood, I've dated Argentinian women in Spain, Mexico, USA and Cordoba of many different socialeconomic groups. (All under 40, so you got me there with age groups..) Yet what I said previously applies to all of them.