Used by middle/upper class white folk to refer to a group of peopleoutside of their social and economic status. Not necessarily a derogatory phrase, but often leveraged to invoke politeness or intentional ambiguity around the individuals to which they are referring.
Me: "What kind of people typically buy the Cadillac Escalade."
Cadillac Salesperson: "We get customers from all walks of life."
When everything seems funny. Usually occurs around large groups of people at night. No substance is needed to create this effect; although, it is rumored that Mountain Dew can help the effect run its course.
With a few friends over and umlimited Mountain Dew, James new that there was no need for weed because they were about to become high on life.