I think this is your confusion. "Redneck" is an American term, it's similar to "Hillbilly". There's all kinds, it usually relates to the uncultured rural people. All cultures have pejoratives for these people. Here, it is "Bogan" (which, again, if you only looked within the culture you would assume would be white only, but that's just because of the racial homogeneity of the rural population).

Every society has their "redneck", regardless of race.