Nguyen One Soon said:
Sorry to disappoint you, but it's the weight grade of the paper used to make the bag, not how much weight it will hold. For example, one ream of 22" x17" 20 pound bond paper weighs 20 pounds.
True story, about 25 years ago good friends of mine adopted twins in Russia. Big environmentalists, they wanted to use as few disposable diapers as possible for the trip back to the United States. I was planning to meet them at a layover at DFW and got the only call ever from one of those old airplane phones: "Hey, if you're going to be at DFW, could you bring us some diapers? We're OUT."
"Sure," I replied, "about how much do the boys weigh?"
I heard the wife cover the phone (not well) and tell her husband "I TOLD YOU the 32-36 pounds wasn't how much they'd hold!"
(If that isn't a Jeff Foxworthy joke, it ought to be ... but the story is 100% true.)