We all usually read the reviews of products for sale on an ecommerce store to be sure we're buying something that is really useful and quality. However, some of these reviews can be fraudulent, and Amazon does not tolerate it. The ecommerce giant expelled 600 Chinese brands from 3,000 seller accounts. The reason? Fake or fraudulent reviews, according to the South China Morning Post . As reported by The Verge , some sellers and brands received positive reviews in exchange for gift cards or even free items. These practices violate Amazon's policy, which has prohibited the practice of incentivized reviews…