/* Why not make Line-Height 34px and eliminate Padding? */
If the text should happen to wrap a line-height that is in relation to the font-size will keep the vertical spacing between text (the line-height) legible.
top/bottom padding plus normal line height keeps you from having to set a fixed height. In turn that keeps your text at v-center at all times when someone like me comes along and uses “zoom text only”.
When I don’t have to set a fixed height I use padding and normal line-height to create an initial calculated height that can expand with font-size changes.
Take this menu for example, reduce your browser window and force the text to wrap down to another line.
If it would of had a huge line-height then it would show up between the wrapping text.