"And then the final recipient has no say in what they receive either... in many cases the donated items go unused."
I used to work in a food bank warehouse, and yes, sorting the goods was a great deal of effort. We sorted them by 'urgency' and use-by date. Canned food was very helpful, because it lasts between the big giving times - people donate primarily in autumn and christmas, and there is a big defecit during the summer, so having long-lasting things was always a blessing.
The main thing that would help would be standardising the placement and format of use-by dates on products. Some few products have absurd locations for the use-by date, such as inside of the container!
Very, very little food was wasted.
Yes, the recipient didn't have a great deal of choice. However, practically, this simply won't be possible without waste, as you'd have to have enough food to offer a choice, and some wouldn't be picked. However, the packages that we provided people were balanced nutritionally, and we took feedback from them regularly about what worked for them and what didn't. We made sure they got a lot of basic, versatile ingredients, such as onions, pasta, rice etc.
In adittion to this, have a little perspective. People who are relying on these kinds of programmes very rarely complain that they don't have choice, as they are glad to have anything at all. We also try to make sure each person recieves some "interesting" items along with basic ingredients, to allow them to experement, and provide diversity.
Things we always needed more of: Long-life milk, or powdered milk. Fruit juice, especially long-life juice or concentrated juice. Fresh vegetables and onions can be helpful, although if you really do want to help its best to confer with the local volunteers on what they need most at the moment.
Things we had too much of: Tea and coffee. Sometimes we'd get a large donation of fruit from supermarkets, but that was usually solved by effort (banannas that can't be given away made into bananna bread or baby formula, or in the worst-case compost for a community garden)