I recently bought a battery grip for my Canon R6. While I was taking wildlife pictures, I was never shooting more than a few hundred pictures in a session, so I never felt the need to have more battery power in my camera. Now shooting sports, I end up with 1000 to 2000 pictures by the end of the day and have to change the battery in the middle of the session. A battery grip extends the battery life to cover a full day of shooting. Another reason I got the grip is that I have been shooting more in portrait orientation, and the grip helps in this case by providing a better hold and a set of buttons in that position that feel more comfortable.
One important point is that I bought a 3rd party made grip, Canon price for these grips is from 400 to 500 dollars while the 3rd party is from $70 to $100! Years ago, a Chinese product lacked the quality that you see nowadays. I have tested the grip in my last wildlife photoshoot, and I'm pleased. Here is a picture of the one I got.
This is the replacement for the BG-R20 which is the latest version of the grip compatible with all versions of R6/R5 and the one adding support to the new batteries LP-E6P. This same company sells the old version BG-R10. Something to consider if you decide to buy their grip, go for the R20 instead of the R10.Here is a video review of the BG-R10 that may help you in your decision taken process.



