Yes, I'm not in the habit of rootling through other people's garbage cans... but this is a special CFZ project, and so I put my gloves on, and went forth...
Our neighbours don't have large and boisterous dogs, so they put all their garden cuttings into the green wheelie-bins provided for such material. We, on the other hand, use all such stuff for reinforcing the perimeter of the grounds to try and prevent Biggles from escaping, and donations of waste from nearby properties are very useful.
Every little bit helps, as the saying goes.
The end result - mounds (or banks) of stuff - look pretty OK, really.
Of course, any animal container is only escape-proof up to the point where the occupant proves you wrong. Kids keeping white mice and zoos keeping tigers have found this out. So... the ball is now in Biggles' court.