https://www.reuters.com/article/us-retail-trading-robinhood-anger/robinhood-is-new-eye-of-gamestop-storm-as-outrage-grows-idUSKBN29X33D >Online broker Robinhood has been one of the hottest venues in this week's retail-trading frenzy but its sudden curbs on buying of some hot stocks have raised the ire of customers, celebrities and politicians who argue it unfairly benefits bigger investors.