Butter in a tub usually isn’t pure butter as they add oil to it to make it spreadable when cold.
Recipes that call for butter are normally designed for true/pure butter and may not cook or bake properly if spreadable stuff is used. (there is however Amish rolled butter that’s sold in big ‘loaves’ where measuring can be annoying)
Butter comes in sticks that are 1/2 cup. So half a stick is 1/4 a cup
True, but that’s just replacing a cup with a length, and rules out using an existing tub.
Why not use weight, which is easy to measure and tolerant of different forms/shapes?
Butter in a tub usually isn’t pure butter as they add oil to it to make it spreadable when cold.
Recipes that call for butter are normally designed for true/pure butter and may not cook or bake properly if spreadable stuff is used. (there is however Amish rolled butter that’s sold in big ‘loaves’ where measuring can be annoying)
Unless you need to measure it in grams then it’s super simple!
Weight requires a scale. I don’t know a single American who has a scale in their kitchen.