Because most Europeans use weighing scales rather than volumetric measurements. When I'm baking I put the bowl on the scales and pour in the ingredients. When recipes say 1tbsp or 2tsp it gets me annoyed because if they had converted to grams I could just pour those ingredients straight in too but instead I need to get out my volumetric measures (or in most cases just guess and hope it doesn't matter too much)

>When recipes say 1tbsp or 2tsp it gets me annoyed because if they had converted to grams I could just pour those ingredients straight in too but instead I need to get out my volumetric measures

Are kitchen scales accurate enough for such tiny measurements? 1 teaspoon is 5ml, so if your scale only has 1g of precision you're looking at up to a 10℅ variance (assuming you're measuring water), and that's assuming its accurate at that range. It gets worse when you need to deal with fractional teaspoons.

> Are kitchen scales accurate enough for such tiny measurements

Yes, and there are lots of recipes that use mass rather than volumetric measurements. For solids, in fact, many sources prefer this because consistency of packing density and other user factors that effect consistency with volumetric measure are far worse than with mass measured with a kitchen scale.

Yes below 5g it's not that accurate but I've never seen a recipe demand precision like 1.3tsp so if anything you can get more accuracy with weight.

Huh, here in Sweden we use volumetric measurement for most things (milk, flour, sugar, etc.), usually in milli- centi- or deciliter.

The exception is usually butter, which is measured in grams (and conveniently indicated on the packaging).

Well, the conveniently indicated grams on the packet are not units of weight - they're units of volume. So you've got two kinds of units of volume in your recipes: milli/centi/decilitres, and grams of butter. But it's fairer than the grams of flour I've been ranting about elsewhere here because at least the manufacturer can have some responsibility for fine tuning it to their product!

Do you have any source for your claim that "grams of butter", "grams of flour" and "grams of sugar" do not all refer to the SI unit "gram"?

I live in Europe and have always weighed exactly 100g on the scale, whether I was asked for 100 grams of butter, sugar or flour.

They are the SI unit of mass. He's just saying that because it's indicated by lines on the package that the actual measurement is done in volume, and the conversion is implicit by the scaling. Where he goes wrong is in thinking that it's implying that "grams of butter" is a unit of volume.

ML is fine for liquids, but you wouldn't (or shouldn't) measure flour in ml.

Well, tell that to Europeans, who don't use millilitres to measure their flour or sugar by volume - they use bizarre units of volume called "grams of flour" or "grams of sugar". Check their cup measures! It's crazy.

Apparently it works perfectly fine for household cooking to use units of volume for flour and sugar. Close enough is good enough!

Isn’t a cup defined as 250mL?

Unless you’re in the USA, in which case a cup is 236.5882365mL exactly.

If you need a particular amount of flour, you can't express it in volume, since 250ml of flour may be too much or too little depending on how tightly the flour is packed. For reliable baking, measuring flour by volume is too inaccurate, you need to weigh it so you know how much flour actually went into that cup.