Accuracy means less waste & better formulation. 1 ounce only has 10 increments: .1-1.0 1 ounce in grams has 28.5 because there are that many grams in an ounce. This allows you to better customize a formula and know exactly how much you added at a more accurate amount. You may only add 8 grams to a formula, but there is no way to calculate that in ounces because the scales don't allow for it. It's not hard to convert when you create standard mixing ratios with your services because you'll know how much to mix to get to the same amount in grams.