Hi
I used to work for a Bank and they have 10 clusteres with 3 node, which means, 30 DNAC on the Datacenter plus 6 DNAC in a Lab.
In my current job, they are also starting to install, propably not that much but at least 10.
Your question make sense but it depends in a lot of factors. For example, if you buy a huge networking Project from cisco with 1k switch, the prices are not the same. Although still expensive.
DNAC is not only for management, if you ever intend to build fabric switch, you are going to need DNAC.
Fabric allows for micro-segmentation with SGT, which is an important security layer for companies like a Bank for example. It, can justfy the cost. And the same for different business.