Please use this thread going forward: [CL] [DU] [FR] [ECO] Objects cluttering worlds | EA Forums - 5036144
From what I found so far, the litter is there if you play neighborhoods that have any lot types that have a shared space (dorms seems to generally count as shared space). It depends which lot you play but changing lot makes them visible.
For example, I tested a new save/new household in San Myshuno and didn't have any litter at all. No overlapping festivals nothing -- until I decided to go to the Karaoke bar (up to that I had only changed to another lot in my neighborhood once, I only had traveled to other neighborhoods otherwise)
Everything became visible when I did that. I then went back to a way earlier save and did the same .. litter appeared. So it was there all along, just not visible.
Didn't have any time over Christmas to test further.
@crinrictThis is what happened to me too. I played in one of the penthouses (originally a dorm, I've changed it to residential) at Foxbury campus, no problem, no litter or bikes anywhere. Then I switched to a regular residential lot (the house close to the river, originally a dorm but now residential) in that neighbourhood, and that's when all the stuff appeared. Even some items that my own sims had lost from their inventory long ago.
