(WAND) - Walmart is coming under fire after it was revealed the retail giant offers employees who work holidays a small in-store discount instead of overtime pay.

Walmart is one of several big-box retailers who are open on Thanksgiving Day. They start their Black Friday sale at 6 p.m. Thanksgiving Day.

At Target and Amazon, workers are paid time and a half for each hour worked.

Walmart offers employees a 10 percent or 15 percent off discount to shop at the store instead. One of the discounts only lasts two days.

A worker at an Idaho Walmart who wanted to stay anonymous for fear of retaliation shared a flyer promoting the 10 percent discount offered to Walmart employees in December, with another 15% discount offered to workers who work shifts from Wednesday to Saturday, to use once on two specific days in December. A Walmart spokesperson confirmed the discount.

Walmart has received criticism from workers, labor activists, and elected officials for paying workers low wages while the family that owns Walmart, the Waltons, are ranked the wealthiest in the world. Their estimated net worth of over $190 billion.

Walmart's minimum wage was raised to $11 an hour in 2018, after the Trump tax cuts provided Walmart with an estimated $2.2 billion in annual savings.

Walmart also rolled out a $20 billion stock buyback program after the wage increase was announced.

In 2016, the company changed its paid time off program to roll paid vacation, sick time, personal time and holiday time into one category.