Seems like you want to use a different word from "survive". Unless you are really meaning that they die. Why wouldn't going to any foreign land be a burden to someone? New customs, language, food, etc.? Maybe you mean, "why do they complain a lot"? Why are these young people traveling to third-world countries? Are they being dragged along by their parents? Are they vacationing? There for a part of their job?

kids like 10 year olds?

>Young adults from Europe and US, when they go to third world country, they expect it to be as same as theirs.

That's quite the comment to make so widely for all these people. I wonder if you could back that claim up.

Billions of people with diverse backgrounds and beliefs can basically never be said to have some universal belief like this. Seems like a stereotype and discrimination to me.

>Local culture/food is a hassel.

When I go abroad, it's literally for the local culture and food. Im not big on museums and all the tourist trap stuff, im there for the people and their food.

>Why is it like that?

What makes the 'developed world' so developed? Go do those things, you become locally wealthy.