What does "60 pounds" mean to Amazon?

Amazon's been running an ad campaign talking about how so much of what they sell comes from independent sellers. They have two ads. One of them shows a popcorn vendor. The other has a group selling some sort of audio device - a waterproof speaker, I think.

Both these ads have "60 LBS" clearly visible...the popcorn guy is seen with a huge pile of 60-pound bags of popcorn, the speaker people have it stenciled onto a Yeti cooler.

It may not really mean anything, but I thought it unusual.