Comic Strips

In KDE it depends on your Plasma theme. Often they are next to each other but it's no problem if you misclick anyway – there's a confirmation screen with an auto-accept timer so you can just undo the wrong action and choose the right one.

Because it's common to group things

every single os

I use sway on Linux. I don't have shutdown or reboot menus. When I shut down the computer via software, it looks like this:

# shutdown -h now

Rebooting is pretty different, looks like this:

# reboot

I guess that my case has a physical reset and power button that are -- while different sizes on mine -- near each other. You could put a button wherever you want to, though -- those things just short two pins. Go to Mouser Electronics or Digikey or something and get one of those big fancy E-Stop buttons with a protective shield that you have to flip up and run the leads to the reset or power pins, put them on opposite sides of the case, and you can use that. I think I remember reading about someone who used a key switch (like, you have to physically insert a metal key to twist the thing and flip the switch) to power on his computer, just for the aesthetic.

EDIT: Apparently that shield is called a molly-guard and the term was actually originally from computer power switches, prior to making its way to other industrial hardware:

molly-guard

Originally a Plexiglas cover improvised for the Big Red Switch on an IBM 4341 mainframe after a programmer's toddler daughter (named Molly) tripped it twice in one day. Later generalised to covers over stop/reset switches on disk drives and networking equipment.