Why has the Parental Advisory sticker been put on cds that aren't?

Question

Such as (quote): After Frank Zappa campaigned against music censorship in 1985, a "parental advisory" sticker was attached to his next album, Jazz from Hell, because of the title of one track, "G-Spot Tornado", although the album is entirely instrumental and contains no lyrics that could be "explicit lyrics".

If you read this:
http://en.wikipedia.org/wiki/Parental_Advisory
you will kind of see where I'm coming from. They have put the sticker on cds that have no real lyrics that could be considered explicit. Why is this?

Answer 1

because they hated zappa and his level of inteligence compared to their own and they felt threatened so they did what they could within the confines of their power