[[WMG: The entire city was driven insane by an EldritchAbomination]]
The tentacles that we see trying to escape from The Plague's basement are [[CthulhuMythos Cthulhu's]] tentacles, and since he lives near the town where the movie takes place, he drove all the residents there insane. This would explain Hope Town's ludicrous, UpToEleven amounts of depravity.
[[WMG: The Hobo's name is Bear.]]
Hence his love of bears and his random bear facts, as well as basically being a bear as his story showed.
[[WMG: The Plaue is Music/DaftPunk.]]
[[WMG: The Hobo gets his ammo from the people of Hope Town.]]
Those who supported his vigilantism but didn't want to incur Drake's wrath by openly helping him would buy shotgun shells and leave them out in public places for him to find, which is why he never ran out.