VPN services, Tor relays, proxy networks, and privacy-focused DNS resolvers all benefit from bulletproof hosting. These services are legal tools that help people protect their privacy online, but they attract surveillance from governments that want to monitor internet traffic and takedown pressure from parties whose activity they make harder to track.
Running a VPN service on AnubizHost servers in Iceland or Romania means the servers cannot be forced offline by a foreign government's order to a US hosting provider. Running Tor exit nodes in jurisdictions with strong legal protections for anonymous communication means the exits stay up even under pressure from parties opposed to anonymous communication.
Security research infrastructure - honeypots, malware analysis sandboxes, network scanning tools for academic research - operates better on bulletproof servers where the tools themselves will not trigger account termination based on automated abuse detection by a mainstream provider.