Why does Paul Walker....

I did live in the US for a significant amount of time.. so to me, all I hear is a typical American accent. The two words that you spelled, "Braga" and "Brogga" would have the exact same pronunciation in American English.

When people from other languages come to the US, they usually change the pronunciation of their names to avoid conflict. I used to know this chick from Colombia with a very Spanish-sounding last name... (double 'l', rolling 'r') and it bugged the crap out of me how when she introduced herself she changed the pronunciation, including vowel sounds and pronouncing the "ll" as if were an "l".. but in the end, it was simply to avoid having to explain the pronunciation and spelling to every single person she met. US Americans are not very open to outside cultures and there are so many different cultures and pronunciations over there that it would be impossible to learn and know them all. Every one is in a constant struggle to retain their individuality while also trying to meld with the dominant culture. It makes for an interesting, complex, and--honestly--pretty ignorant culture.