It is generally considered a recessive trait, its persistance in European countries is attributed to blue-eyed people finding blue eyes more attractive than other colors.
Blue eyes are much less common than brown, and much more common than green. Talking world population wise, brown eyes are common everywhere, blue are only in high percentages in Norhtern Europe and the "colonies" (Canada, the United States, Australia), and green is only present in large numbers in Iceland.
Mark: I dont know dude, they arent all that great.
You will always want to have them as your friend, and they are the best lovers, and can do anything the best.
They are sweet and powerful and way better than anyone else.
Blue eyes are rare, and if you have them you should consider yourself lucky.
Person #2: Yeah, s/he is amazingly perfect.
2. A nazi aphrodisiac.
A: "What color are your eyes?"
A: "So you have blue eyes?"
A: "Hey SS soldier, I have pics of blue eyed people."
B: "Where is the nearest bathroom, I have a boner... Ill need to borrow those pictures as well."
A: "So you must love blue eyes right?"
B: "Only when complemented with blond hair and a reich."