Annoyingly in places it looks like data they have and turns out but to be. I once bought a desk lamp which below it included the "people buy these together" box

Annoyingly in places it looks like data they have and turns out but to be. I once bought a desk lamp which below it included the "people buy these together" box, which showed the llano and a bulb. Frustratingly it wasn't the right bulb, but I just fed a further data point into Amazon's model, and reinforced their belief that its useful to list those two items as a pair.