I have been working in an international environment since I started my undergrad project, in 2005. Science is an international field and it is very common for people to move around. Some do it for a couple of years, to gain experience, and then go back to their home countries. Some do it for longer and adopt another country as their own.
I see foreigners as equals. I do not think of foreigners as superior, just because supposedly they have more life experience, and I certainly do not think of them as inferior. I think of them as equals. They might have the disadvantage of not speaking fluently the language and of not understanding the cultural do's and don'ts, but they have the advantage of seeing the same place with different eyes and of observing things more clearly, from the outside.
A foreigner has a completely different lifestyle than a native. A foreigner centres the energy on the surroundings, on the new culture and on the internet trying to keep up with events happening 5 countries away, in a place they once called home. The native is at home, and focus the attention on the people, family and friends, and barely notices the surroundings anymore.
As a foreigner myself, I see three kinds of people. There are those who see foreigners as another element, someone who might have lived different experiences but now is in the same circle, living the same things, even if differently. There are those who see foreigners as poor creatures - they had to abandon their comfort zone - or crazy creatures - why would they do that voluntarily. And then there are those to whom foreigners do not exist, what exists is "stupid foreigners". They don't speak the language, they don't understand that is rude to refuse bourbon from the boss at 10am, they are not invited to the cool parties and they spend money flying home instead of buying cool clothes (all happened, but not all to me).
The biggest barrier between foreigners and natives is the language. No doubts about that. Sometimes it’s an even bigger barrier when they all speak a common language, such as English. There are countries in which a group of 10 people, that includes only 1 foreigner, speak English all the time, including when the foreigner leaves for a few moments to make a phone call. There are also countries in which people refuse to speak a word of English, even if they are fluent, unless they really have to. Or unless they need a favour, of course. They tend to avoid eye contact as well, acknowledging the native that is with the foreigner, and pretending the last is transparent. They refuse to understand that a person that comes to their country for a couple of years does not have to learn their language, especially when the official language at work is English (even for them!). I have observed conversations between a foreigner and two natives in which one of them has to answer the same questions both in English and in Czech, just because the other native refuses to use English. Unless the boss is involved, of course.
The years have taught me to ignore it and think they have not lived enough to understand the situation. It's ok. But secretly, deep down inside of me, in that locked drawer where I keep shameful thoughts, I wish someday they find themselves completely lost in Yemen, barefoot, without a map, a GPS and money, looking for the way home.