There's an organization in NYC called City Harvest that "rescues" food every night that restaurants, supermarkets, farmers markets, bakeries, and the like are unable to sell, and distributes it by the truckload to soup kitchens and food pantries. Hundreds of tons every week.

They are very strict about what donations they'll accept. Even what's left in a buffet at the end of the night can't be donated. There's too much risk of contamination and spoilage. With your leftover burger there's no way to be confident you've practiced appropriate food care (refrigeration; how long you've kept it) even if you never unwrapped the thing -- let alone the slice of pizza that you probably touched with your bare hands and for all anyone knows is harboring flu virus or strep.

You're right, the liabilities make it unrealistic. How about buying a little bit less food and either donating the money you'd save to an org like City Harvest or buying a sandwich for the next homeless guy you pass on the street?

If only food irradiation was less restricted, perhaps they could irradiate everything and at least be assured its safe even if it was spoiled.

IIRC, radiation doesn't help with botulism, which is a chemical rather than a virus or bacterium, and which is incredibly toxic.

It kills the bacteria that produces it, but that is a good point. Still, it might be possible to test for it, and its unlikely that restraunt food contains it just from getting spoiled.

As I understand it botulism is mostly a concern in canning. If you kill most of the bacteria but the botulism bacteria is hardy and survives and produces it for months in the can.

You won't get that from eating spoiled buffet or even garbage.