Sure, i see some people who try to use it against a culture, as you've suggested (the stereotypical 'bumpkin' type) - but the use is quite liberal (not political, as in - liberally spread around) to all whites. Just as the term 'nigger' is known as a racial slur against all blacks - however - some people try to claim it as purely a cultural slur, now, and only use it to describe a 'ghetto thug' or whatever.
I've been called 'redneck' just because of where I live - based on the fact that I'm white and live in a small town.
Per the 'cultural use' of it - I'm not poor, uneducated, racist or anything that would be 'redneck' according to your thought process. So, to me, it's purely racist and unacceptable just as the use of the term 'wetback' and 'jap'
I prefer people just don't use it - but hick or bumpkin, yeah, these have never been explicitly race-based and thus cultural slurs.
however, why does that still make them acceptable? As if slandering someone's culture is OK or acceptable?