Serbia has a few traditions circled around bread. Culturally, it is considered taboo to toss out bread, so you'll frequently see bread hung in bags on the side of dumpsters (for hobos & for bird-feeders alike).
It's also acceptable for the homeless to ask for leftover bread in the bakeries. If you are a foreigner, your mileage may vary. Try Serbian phrase "Imate li bajatog hleba?" which translates roughly as "do you have any leftover bread?" (Bread is "hleb(a)".)
Fruit and vegetable markets do seem to yield but it's the worst of the worst unlike the vast amounts of perfectly good vegetables that get thrown away in western europe.
If you go to the store to buy just one head of garlic, you'll likely be given it for free as it's really nothing in Serbia.
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