Most dumper divers are looking for food, industrial or retail waste.

A Vancouver bakery I once frequented use to put all their perishables into a clear bag and place them on top of the dumpster. That dumpster bin never got raided.

Dumpster divers tend to stay away from dumpsters that contain bad smells or if they knowingly contain any amounts of human feces, syringes, rotting meat, bandages etc.

A bin from a produce store smells like a produce store. A bin from a butcher smells rancid and will never get raided (unless the diver is mentally ill).

Dead fishes smell pretty bad. Rotting potatoes are perhaps the worst. Anything that rots in this manner should detour them if they are sane.