Trash Talk

How is it that all garbage smells the same? No matter what the hell it is, it all breeds the universal stench of … garbage. I don’t get it. I discard coffee grinds, a banana peel (so I wouldn't slip!), wrapping from my raw salmon filet, four tissues and a cashew that fell on the ground. Within 24 hours this combination smells exactly the same as 6 discarded lemon wedges, a slice of old cheese, my expired Bed Bath & Beyond 20% off coupon that I think I will use but never do, half a piece of peanut butter toast, 3 egg shells, and one peach pit. How could this be?