Streamers and pros use cheats. Google "streamer caught cheating" and there's page after page of news items about people cheating even in tournaments, while streaming.
They're "whitelisted" because the game benefits from streamers who look like they're great at the game, and because competition for pro players is actually fairly stiff (in part because there aren't many pro players, because it's so hard to make money at it...but also because being competitive at a game usually means dedicating your training and play time to that game.)
Aim fatigue is a problem for pro players and it usually sets in around an hour or two...so when you see a streamer playing really well hour after hour, they're almost certainly employing some level of cheating. It might be really subtle, they might only 'flip it on' when they really have to. But it's there, and at 30-60fps and stream compression it can be really hard to spot even if you're a seasoned player in the game.
