I haven't snapped a lid on a fermenter in a long time and don't use an airlock. I just set the lid on the bucket and let it do its thing for a couple of weeks, never an issue. While this isn't truly "open" as I have it covered to keep the big stuff out and pitch my own yeast. The CO2 produced makes a protective layer on top of the fermenting beer, no worries about oxidation in the short time it is in primary. Beer is tougher than most give it credit for. So this is what you are seeing on a larger scale at the brewery. I'm pretty sure they pitch yeast and don't rely on the wild variety.
If you're stupid, you have to be tough.