I think your theory explains some but not all seasonal foods. Many are originally seasonal for logistical reasons: before refrigeration, food had to be eaten c

I think your theory explains some but not all seasonal foods. Many are originally seasonal for logistical reasons: before refrigeration, food had to be eaten close to harvest time or preserved in some way. So you have pumpkin dishes in fall because that's when the pumpkins are ripe. Likewise tomato dishes in spring. Winter holiday foods often get that association because they are preserved. We ate them then because we had nothing else to eat since the harvest is over. That gives you eggnog, cured meat, jams, etc. Once a dish gets a strong association with a certain time of year, I think it tends to hold it because the association is part of the enjoyment. Sure, I could have a mug of eggnog in June, but it wouldn't be as magical.