Yes, absolutely it's bad they're throwing it out. No debate there. But it's not like they can ship it somewhere else without it costing more than the food itself.
The solution is better understanding of who needs what and try to fill them as close as you can without going over too much. That will optimize usage of a product.
Other countries have done it. The US won't. It's clearly not anywhere close.
You essentially have to "undo" that chain faster than the product will go bad to a place it will be utilized in time.
Otherwise you'd have to travel to the majority of pharmacies all around the US and some how get that all to the airport.
And trucks/delivery drivers are very very expensive at scale.
I imagine the effectiveness of anti-vax propaganda is tough to incorporate into distribution forecasts.
There is also no reason to fly to these locations. There is already the logistic capacity to ship in the proper conditions between these locations and a few central hubs. It just has to be run in reverse. It hasn't been done for hundreds of locations because few countries are as big as the US, but it has been done on a smaller scale by less capable actors.
You can't just duplicate existing routes. The logistics to collect unused vaccines from endpoints (on an insanely tight clock), would be enormously complex. We'd be setting that up on a nationwide scale, in the middle of a worldwide transportation shortage.
Further increasing exportable vaccine production would seem to be a more attainable goal.
What if, for example, food that would spoil in a couple more days were simply moved to a "free" section of the grocery store? No need for complex shipping or logistics costs, simply ask the stocker to move from one aisle to another. Why don't grocery stores do that, if they're concerned about "reducing waste"?