YouTuber MrBeast's company emphasized the size of his audience and stunty videos in pitches to brands. Arturo Holmes - FIFA/FIFA via Getty Images Newly filed court documents reveal how MrBeast pitched brands and what his rates were in years past. They show how the YouTuber has become a marketing machine for brands. We broke down the takeaways of proposals for Slack, Sony, and Walmart. How much does it cost to run an advertisement with MrBeast, the world's top YouTuber? Newly filed court doc...