Jazz Music Stops - “isn’t 20 a bit old to be trick-or-treating?”

Off the Hook still does Trick or Treat and they are 21 and 18 respectively, so yes, that argument is invalid.

Adult trick-or-treating is buying the candy you want, not a pot luck of the good shit like Milky Ways and jawbreakers or the shitty Now-and-Laters, then wallowing in intestinal misery as your body realizes it can't consume as much candy as it could before.