Agreed that there are a small percentage of people who are professionals, for whom the risk of live practice is probably worth the risk, also considering the likelihood that they would have to deploy their skills in this way.

For the rest of us (and I didn't see anything to suggest that these two martial artists were practicing in a professional context), the likelihood of needing to deploy this skill in a real attack is small, and if you want to practice such a skill as self defence you should be doing it with a fake gun, or at most in a way described by novas0x2a's link to the Tueller drill.

To invoke a programming saying, "you ain't gonna need it."