Sure, I redirect when there is to redirect, but sometimes during debugging you want to spam yourself to see what is happening during some stress testing when some code path is full of printfs. Also sometimes I'm just on the redis-cli and to test the system at scale I directly ask (like yesterday) for half million of similar vectors. It is very convenient I can type this on the CLI and see the result immediately, instead of flooding myself for seconds or minutes.

Telling to creator of Redis that they might want to reevaluate their respective program logic (Redis) is pretty funny, only on HN :)