Make it cheaper so they don't go unsold.
But NO. Profits.
And also leaving foods unharvested is less waste than unsold. Rotten food can become nutrients for the soil.
Cost of Disposable seems like a logical place to start pushing.
Landfill disposal rates (i.e., tipping fees) have remained exceptionally low in the U.S. relative to many other developed countries. Since tipping fees are typically the largest revenue streams for recycling processing facilities, this has hurt the business case to expand organics recycling infrastructure.
Don't make it cheap to toss unsold food into the trash. Weigh and tax unsold food from grocery stores to give them a cost incentive to develop better methods of disposing unsold products.