A very labored differentiation, Dave. Once you create a climate where it is inopportune to put certain magazines on the counter for a story they publish, you are on a slippery thoughtcrime slope. Rolling Stone is not advocating terrorism with that feature and neither is anyone selling (or buying) this particular RS issue.
Besides its nothing new. If Jack the Ripper wasn't a rock star type/celebrity/icon centuries ago, who was? Murderers have always had their - albeit fleeting - fame. People have always been fascinated by violence, muderers and terrorists, what have you. The difference between people back then watching public hangings and consuming media violence today is slight. Overall, western culture and life have probably become less violent, but people's dark obsession with violence has not decreased.
And of course it's interesting to read and see what made this guy do the things he did.