I'm with MellowVision on this. I suspect the store falls under the jurisdiction of some Weights and Measures agency -- whether local or state. If they say they sell something by the pound or ounce or gram (or whatever) and check its weight prior to sale, then they can't round up. It's the same thing as buying vegetables by weight or nails by weight. AND, by the way, in Oklahoma anyone commercially selling anything by weight must use approved scales -- not just any old cheapo bathroom or kitchen scales. Further, the scales must show the most recent inspection sticker. Big fines and/or store closure can be levied / ordered for violation of the law down here.