Food shortages are really really bad even for small amount of time which is why food is over produced in excess.

Not exactly. For example, if you have a picker machine harvesting 80% of crop, and manual work ain't cheap (it's Norway), you'd probably throw 20%. But you can't "ungrow" it in any meaningful sense. Agriculture is complex.

One "solution":

Invite people to come down to hand-harvest the rest of it. Charge them a nominal fee (if at all).

Yes that is what we do here. It’s inspiring but the impact on food waste is negligible.

This sounds more wasteful to me. In terms of manpower and cost of commute.

If it's cheaper for that person to commute in order to eat then it's probably less wasteful from a financial perspective at least. Definitely possible to be even less wasteful of course, but I think without perfect weather and population models (which will never truly exist) it'll be hard to eliminate waste to a certain extent.

Something like this is usually not done out of economic incentives, but because of ethical and emotional incentives. In the end people do it to feel good, but might do more harm, just in another way.