To give a Reconstructionist answer: people adhere to these restrictions because they find them meaningful. It may be one or more of * to feel a connection to o

To give a Reconstructionist answer: people adhere to these restrictions because they find them meaningful. It may be one or more of * to feel a connection to one's ancestors * to be connected with one's community (people bond over food, so a group of people who eat the same way can connect more easily) * to be reminded of a tenet of one's faith (as with many other rituals) * to make it feel like the holiday (Is not eating bread on Passover so different than always eating turkey on Thanksgiving?)