When people think about Buckwheat Pillows, they often don't realize that a Buckwheat Pillow is not filled with Buckwheat itself, but rather just the hulls.
This makes a significant difference as there are "Buckwheat Pillows" on the market which are actually used as heat pads. These type of pillows are usually filled with Buckwheat grains and not the hulls.
Most Common Buckwheat Pillows for sleeping, are filled with the HULLS of the Buckwheat Grain.
Same thing goes for Millet Pillows :)