There's a machine for this, and you can rent it - the Barber Litter Picker.[1]
It's a large tractor-pulled machine, like an agricultural implement.
It's a variation on their Surf Rake, which is used for beach cleanup. The Litter Picker is built for dirt, hard ground, grass, and pavement. It's used for large outdoor festivals.
Scoops up everything from cigarette butts to lawn chairs.
Video of cleanup after a big festival.[2]
Big festivals are cleaned up in a few hours with this heavy equipment.
Big festivals are cleaned up in a few hours with this heavy equipment.
[1] https://www.hbarber.com/litter-collection-equipment/litter-p...
[2] https://videos.files.wordpress.com/IxQgz6Oo/lp-concert-jiffy...