Why does cheap jewellery have to be made from nickel?

As fashion jewellery becomes more popular why do they still use crap metal when they know most ppl have allergies to it. surely in this day and age someone could come up with an alternative. . save a lot of sore ears. . . ..including mine!!!!!!!
Answer
Thank u for your question i would love to know this to for years i have suffered even down to a belt i cannot wear plus ears plus necklaces but i know of a way to protect yourself for a few hours brush the item of jewellery with clear nail varnish