There is a story (or two) here.
My first thought was that the guys got their pants wet, hung them up to dry and are hiding pants-less behind a pole.
Then I thought maybe they just decided to take their pants off and hide behind the pole for a lark. Granny strolling through the park - surprise!
Or maybe they spotted four guys at the swimmin' hole and are waiting for the right moment to steal their pants.
The remainder of the record consists of filler. Some if it rocks, some of it just lies there like blue jeans in the laundry pile.
Have a listen to the Hippy Hippy Shake