There are multiple drop-down style menus which share hotkeys between the different menu items. A really common example is the automation point right-click menu where if you repeatedly press "s" you cycle through the curve types: smooth, single curve, single curve 2, and so on - but to select the one you are on you have to press enter.
Let me confirm the selection with the space bar instead of enter, so I don't have to move my right hand from my mouse to my keyboard and back to my mouse every time. The space bar does literally nothing in those situations.
Here are some of the menus I'm talking about:
