No. The vast majority of the poly folk I know are not hippies. They're friendly with hippies and can be found hanging out with hippies at times, though they are not hippies.
When speaking of various forms of non-monogamy...it ain't poly if you're just fucking around.
While polyamory, open relationships, and swinging are all distinctly different approaches to non-monogamy, they are not mutually exlusive. Folks can, and some do, engage in more than one of them at a time--and it's all good.