Here are my thoughts (sorry for the long post):
People like to put things into neat little packages. When a person experiences something for the first time, they develop (or adopt) terms to describe what they've experienced... as their knowledge of a specific subject builds – so does their vernacular until they gain the ability to "speak the language."
The issue with the media is they are expected to know enough to inform the public & to write a good story – nothing more. What they don't know, they adlib. If they don't know a term, they'll adopt one and define it with their own words. So depending on the story, innocent words are left vulnerable to adapt negative connotations.
I wouldn't pass blame entirely on the media. Word of mouth is much stronger. Words are powerful and definitions shift and change with age, time, popularity & use. If you ask my Grandfather – it's all as "Stump Jumpin."
*edit* Going along with this idea - different regions develop and stick to their own terms.