It's also all shot handheld. They like fast setups so they don't deal with dolly tracks and even steadicams from what I understand. They also want deep depth of field since it makes following action easier. Basically they're going for a "live reality" look.
Personally when looking at cameras, key is whether it meets you objectives. If a high priced camera has features you really don't need and complexity which slows production, it's a hinderance.
The EX 3 chip cameras resolve very well. The sensor can match much higher priced cameras. If the codec is a drawback (and often it isn't) it's not that expensive to get 10 bit 4:2:2 out.
There are certainly shows (extreme sports for example) that use GoPros. How well do you think someone can skateboard with an Alexa mounted to their head? Right tool for the job. Price of the camera is a byproduct, not a goal.