Answer:
Many laws set practical <em>standards for weights and measures</em> in the British Parliament such as the <em>weights and measures acts</em>, which determine and enforce the unit of measurement for weight;
the <em>"Pound", </em>equivalent to 16 ounces, is used to measure several things such as food, people, animals, with the sign <em>"Lb" (from the Latin: Libra)</em>, and albeit it has the same name, when it come to the currency, the <em>"pound sterling"</em> gets the (£) symbol for the sake of disambiguation.
Thus that's why <em>"buying one pound of bread"</em> is part of <em>the standards for weights and measures</em>.
Explanation: