It seems like the only better alternative might be a fixed price based on count/average yield. It’s not perfect, but it seems possible that you could pay a farm

It seems like the only better alternative might be a fixed price based on count/average yield. It’s not perfect, but it seems possible that you could pay a farmer more (net of water costs) and the supplier could save money (net energy and transport costs). It wouldn’t work with all foods, but the volume of tomatoes alone could be meaningful.