Almost daily on my iPhone.

The side button (https://support.apple.com/en-gb/guide/iphone/iph7d116e557/io...) is on the exact opposite of the volume up button. Pressing the side button to shut down and lock the screen is something I do a lot. Press button (2) with the thumb and you will see that it is very natural to have your index or middle finger resting where the volume buttons are.

And occasionally I press hard enough with my thumb that the finger on the perpendicular side of the phone presses the volume up button and whoops I have taken a screen shot instead.

That said. I do consider this "feature" an abuse of privacy API:s, and I also often get annoyed that I cannot take screen shots of my bank app to for example send account information, or confirm a transaction, or report a graphical bug to the developers at the bank.