You do if you are stupid flush with cash. I once went through 50 rounds of Black Talon(s) at the range for my primary carry. Practice with what you shoot was the theory.
I also had an AR-50 back in those days and could afford the $5 per trigger pull.
Today, in this economy, ball ammo is good enough for paper targets. I could eat for a month on what I put downrange when I was young(er) and (more)foolish.
/johnny
I get the concept. But you can still do practice with a round of equal or near equal power and a lead bullet than with an expensive copper bullet.
Shooters feel the difference with different power loads. You can get lead loads equal or near equal to what they’d actually be carrying.
Bigger question is why is Social Security carrying freaking guns and needing that much practice in the first place? They are not police officers.