[Shivetya]

It is never pointless to conserve. If anything it benefits you.

As for businesses, giving away expired or unused food has liability and tax concerns. The liability is probably the primary reason for not doing so. Having worked in a bakery over twenty years ago they used to give expired bread to a local charity until they were blocked by county health officials. Mind you, nothing was wrong with the bread, it was merely too old for them to sell.

Then you top it off with the fact many charities want money, not old food - even canned food that is not expired is not wanted except by select charities or at certain times of the year.