So obviously this is an extreme, but I worked for a company that had long dismissed third party cloud providers as too expensive (customers would be routing all of their network traffic through our data centers, so obviously the bandwidth costs would just be too dang high). Then that company got purchased by a certain mega corporation who then negotiated an exclusive deal with GCP, and the math flipped. It was now far too expensive to run our own set of datacenters. Google was willing to take such a low margin on bandwidth that it made no sense not to.

So in this case, hundreds of billions. But the principle stands at lower company sizes, just with different numbers and amounts of leverage.