I attended a university which DHCP'd unique, public-facing IPs to every device on the network. Although this requires tens-of-thousands of unique global IPs, the university only utilizes a small percentage of their allocated IP range. Having worked in the IT dept during school, I know it would have been a nightmare to attempt merging ours with another IP-range.

Back in 2006 I gave a presentation on IPv4 end-of-life, when it was then predicted IPv6 would be entirely necessary by 2020 (i.e. that IPv4 would die out by then). This explainer/demo, almost two decades ago, got me a job offer... and yet two decades later I still don't use IPv6, myself!