1. In Europe the only place where you will not be treated as a foreigner is where both of your parents (and grand parents) are born. Meaning that a German will always be a foreigner in Spain (not even speaking about language difficulties).
You have no idea of what you're talking about.
Actually, it's much worse than that. An East German is still seen as a foreigner in some parts of what was western Germany, an Italian from Napoli isn't welcome in Milano, and Parisians are treated like mad men in the rural areas of France, but frankly nobody cares about that anymore. In Southern France or in Tuscany, there are small villages where the foreigners vastly outnumbers the locals, and everything's fine.