The top selling floor lamp on Amazon weighs 5 pounds and emits 400 lumens. The tall Channel lamp weighs approximately .7 pounds (.109 per foot) and emits 438 lumens (73 lumens per foot).
400/5= 80 lumens per pound.
438/.7= 625.7 lumens per pound
This metric doesn't really effect the experience of using the lamp. A few lumens difference is negligible. However, the metric is important when applied on a large scale. The weight of a product impacts shipping, manufacturing, and environmental costs. This metric is more important to me than price.