Of course, this is simply prejudice.
A simple way of making melted butter is as follows:--Take half a pint of cold water, put it in a saucepan, and add sufficient white roux, or butter and flour mixed, till it is of the consistency of thin gruel.

Now gradually dissolve in this, adding a little piece at a time, as much butter as you can afford; add a suspicion of nutmeg, a little pepper and salt, and a few drops of lemon-juice from a fresh lemon, if you have one in use.
BUTTER, MELTED, OR OILED BUTTER .-- Melted butter, properly speaking, is rarely met with in this country, but is a common everyday sauce on the Continent.

It is simply what it says.

A piece of butter is placed in a little sauce-boat and placed in the oven till the butter runs to oil, and then sent to table with all kinds of fish with which in our present work we have nothing to do; but it is also sent to table with all kinds of vegetables, such as French artichokes, &c.; sometimes a spoonful of French capers is added to the oiled butter.
BUTTER, BLACK, OR BEURRE NOIR .-- Take two ounces of butter, and dissolve it in a frying-pan, and let it frizzle till the butter turns a brown colour; then add a tablespoonful of French vinegar, a teaspoonful of chopped capers, a teaspoonful of Harvey's sauce, and a teaspoonful of mushroom ketchup.

Let it remain on the fire till the acidity of the vinegar is removed by evaporation.