I'm pretty sure it random which debris gives donuts. There was a thread a few days ago with a way to possible exploit getting donuts every time but it was a bit much
It's random. I have cleaned up probably 150 pieces, if not more, and have received one donut.
Through my testing (and with a couple of other users verification), I feel 99.9% comfortable saying the donuts are RANDOMLY PLACED. I will let you know in a few weeks whether or not the AMOUNT of DONUTS on the grid is random, or if there is a fixed number.
I've never gotten a donut from debris.
I wonder if it's because I usually move it first? I have some debris I'm using as decorations so when I want Homer and Lisa to clean the rest up, I move it to right in front of them so they don't get what I want to keep.
Would that remove a donut, I wonder?
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