This was my earlier response (copy and pasted below) to a similar comment on my original article. It's clearly more than just one person who thinks this way, so I'd be interested to get to the bottom of it.
Let me know your thoughts!
"While I am familiar with the way B12 is created bacterially in the digestive systems of animals, even assuming that soil isn't cobalt-depleted, most animals raised for food are not able to graze naturally or even come into direct contact with any nutrient-dense soil as they should in order to naturally produce the vitamin. In addition, 75% of the antibiotics globally produced are given to animals as a precaution against disease and thus a vast majority of the B12 producing bacteria is rendered useless.Lastly - and perhaps it is just an American thing (wouldn't surprise me) - however the USDA details that swine and poultry are most certainly given B12 supplements. I believe around 90% of what is globally produced is bought and presumably used by the animal agriculture system."