In all likelihood it's an indication that the owner of said trash can really doesn't care what you throw in there, but the period after "bottles" makes me see it as a transcription of a minimalist poetry reading.
I call this one... "Glass Bottles."
*standing snapping ovation*
Thanks to Mike for the photo.
And welcome to our visitors from Boing Boing. Poke around a bit. Pay particular attention to the Hall of Fame on your right.