And 'treated better' is just how you manipulate your own existence; if you don't want to be treated badly (or being treated better), anywhere, you can accomplish that. Except of course in state of war or oppression, but none of these countries have that (at the moment).
If enough people persist though, changes happen. If no one does it, it stays the same. At least longer. And I know not all think like that; I made great entrepreneur friends in PT who run great companies with great people. They are changing things. And people are listening; we have coffee and beers with the major and university director and so forth because they need their town to change and they want to stimulate this change all they can. A lot of people want this, the fact that some are stuck in their ways has to change. If I can contribute 1 millionth of a % to that, I am happy.
No, it's an attempt at appeal to a pre-existing emotion. Not the same at all. Not everyone of us is a rootless opportunist that will go to any place he might get an advantage from going at a moment's notice.
Some of us have bonds with the place where we grow up, and the place were our friends and relatives live. We also have bonds with our culture (from the language, to the music to cuisine). It would be a sad world if everybody was only thinking of his own marginal benefit and could not care less about such things.
Plus, beside the emotional and cultural bond, a lot of us want to give back to our community and improve it for the future generations, and not flee at the chance of a better salary elsewhere.
For an American it might be "freedom", but for a lot of world cultures, the ease with which an e.g American changes states is a sign of lack of roots and fear of emotional attachment, not to mention selfishness and lack of care for one's parents. Plus the mighty appeal of the dollar and the "american dream" of making it big, ie the opposite of actual freedom.
Not that there aren't tons of American's deeply connected with their state and city (mostly people in the South, in my experience, but I also know New Yorkers and Chicagoans that wouldn't change their city for anything).
So what? Why should you care about the health of "your country"? That's just an attempt at emotional manipulation.
You can help Portugal with your IT skills, or you can help a similar number of people in the US/UK. If you get treated better doing the latter, there is no reason to stick to Portugal. The people of the US/UK are no less deserving of your skillset than the people of Portugal.