Kodak may well be one of the last companies to abandon "(near) total vertical integration." It's never been clear to me exactly what they made, but I think at one time it included their own paper, their own film base and most of their own chemicals. Not sure about gelatin.
I think one of the last things Eastman did before he died was purchase what became the Tennessee Eastman Division in Kingsport, TN. because he was having trouble getting the quantities and consistant quality of chemicals that they needed. EK spun them off sometime back in the 80's.
But I think one of the quiet secrets about the entire move to digital photography is that much of it is being driven by environmental concerns. I'm sure it was a huge driver in their closing all of the labs.