Some people only use a read only LiveCD session on a laptop without a hard drive and randomly going to places with free wireless internet. Other people don't trust in virtualization and sandboxing. There's a manual way of making your own sandboxing with a few commands without using firejail. Some think that Tails is compromised and that Whonix is crap because VMs are crap even with KVM. A few does what Stallman does in using other people's computers with their permission to view some proprietary stuff.