I think corporate media plays it up too. Easy nostalgia value, no need to create anything new, and lots of bright colors. And wouldn't ya know it? They just eat it right up.
You do have a point here, makes it an easy sell for material. Nostalgia plays such a pervasive role in perpetuating certain elements of pop culture, and with this in consideration, corporate media taps into our sentimentality for different eras and we buy the product to relive a golden age.
“Thoughts are the shadows of our feelings -- always darker, emptier and simpler.”
― Friedrich Nietzsche
The illusion of a simpler, more prosperous time. It's the same reason there was a 50's revival in the 70's, a 60's revival in the 80's and a 70's revival in the 90's. People who were children in any given era are less likely to remember the strife or crises since they were most likely not exposed to it. I grew up in the 80's and my memories tend to be about ThunderCats, Michael Jackson, and Indiana Jones--not Iran Contra or The Cold War. Likewise people coming of age in 2014 might have a shiny, disneyfied, whitewash idea of the 90's, assuming they're even old enough to remember that far back.
Also, what @five sounds said. It's easier to repackage old product every few years and market it to the next generation or to the generation x'ers whose Nirvana CDs have worn out and need a new remastered version. These companies (entertainment companies) are sitting on a vast store of old TV shows, movies, and music. Why not make money on it? Easier and less costly than producing new product. It's for similar reasons that seemingly half of the major films released now are either remakes/reboots of popular beloved franchises from decades past. Easier to repackage old shit than try to come up with something new.
Everything cool has already been done. We live in an age in which everything is just a slightly revamped version of some previous thing. We as a society are too scared to face the problems of tomorrow so we regress to what we already know. Anyone can be a hippie because they know everything about hippies. Early hippies probably didn't know what they were. It is seen in youth culture (hippies/90s), politics (the tea party), music (cover bands), etc.