Unhappy customer

I bought superga sneakers online in February this year. I wore them once to my son's school function. They got dirty and needed a wash wiihich I did in normal omo and water and drumming them not in direct sunlight. I only realized a few days later in shoe was lighter than the other. I didn't want to take it back cause I thought let me just paint them. Changed my mind cause no man I only wore them once. So truworths apparently send it to there quality department which declined taking it back cause apparently I didn't follow washing instructions after my shies were at the store for weeks and no one called to let me know. After many calls with one of the ladies and a manager I was told sorry they can't replace the shoes cause I bought it on sale and they can't overwrite the price. Clearly woolworths is a better store and option to use when buying anything because we as customers don't not mean anything to truworths to them its all about the money and not keeping their customers happy