almost all veggies have enough bacteria to ferment.
The advice I've been getting about doing a lacto-ferment with malted grain - ie, sauergut - is pretty much leave the grain in water at the right temp and the ferment will happen. Now, thing is: during the kilning all of the bacteria that will have naturally been living on the grain will have been killed. And I wouldn't be surprised if after the kilning some malt makers take reasonable steps to keep the grain clean. So I conclude - often the bacteria that does the magic will introduce itself after it comes out of the bag! I guess many lacto-ferments happen in the same way: a bacteria just comes along, finds an environment it likes, and hey presto! Kraut!