The fashionable racists probably mean no real harm, because they choose their philosophies based on whatever's getting the the most interesting publicity at the time. Don Imus may have killed the fun for them, though.
Remember how the Oklahoma City bombers kicked the legs out from under the militia movement in the United States? Talking smack about attacking the government was one thing. Actually turning your fellow citizens into dog food with your home-made bomb was something else entirely. Doubtless the true believers in the militia movement are still fomenting happily, but the posers melted away as fast as they could toss aside their Confederate caps.
Way back in the late 1960s and early '70s, a large anti-war movement demonstrated against the war in Vietnam. Conservatives complained at the time that the whole peace community was infiltrated by traitors and Communists, external enemies of the United States of America. At the time, peaceniks mostly chalked it up to right-wing paranoia. Later we all found out there was some truth to it. Of course our county's enemies would take advantage of a convenient movement to oppose a major policy of our government.
Right now the fashionable racists play into the hands of the die-hard racists who have never given up on the idea that human division is far better than equality and real freedom. They encourage the fashionable use of racist terms across the divide and the idea that a balance of racism is better than an end to it.
Fashion will probably shift away from the slinging of these particular insults, unless tempers flare enough to lead to some irrevocable harm to human relations. Genocide, anyone? Some people would welcome it. Fad racism ratchets up the tension and makes an incident more possible.