Cultural Adaptation and Cultural Adoptees

There is this thing that I have never understood and that is this total fascination and absorbtion of another culture that I have mostly seen happening to some europeans getting in touch with Latin American or African culture. What generally happens is that they get completely in to this culture and everyting connected to it; the language, the music, dance, food, sports and religion and specifically only are attracted to persons from that specific culture. Often they can go to quite some extent in defending why this culture is so much better, so much purer and more "real" than others.
I have never understood this and I have also never understood this faiblesse for these cultures. Partly I have explained this with the fact that I don't speak the language and hence is not able to understand this. I willingly admit that I still don't understand Portuguese very well, but I still think I would never be one of those committed culturalists. Not that there is anything wrong with the Brazilian culture, it has many positive and fascinating features, like most other cultures. And maybe here is my problem with these people. They tend to over romanticise the culture they have fallen in love with and start to despise and reject their own native culture without sometimes even knowing it very well.
This I don't understand and most of all I don't see the need for this reaction. I have a theory however and that is that these people are somehow seekers that are somewhat unhappy and unsatisfied in their life and with the culture they grew up with and find an easy fix in adopting another culture. What they tend to miss in the process is how much they are formed by their own culture anyway, like it or not. And also that all cultures have their advantages and shortcomings. Now I will want to interpret my scepticism toward this as a sign of good diplomat material. I like different cultures and like to know more and understand more about them, including my own, but feel no need to get over enthusiastic about one before the other.