I keep seeing people with their lens shade reversed while shooting. Anybody knows why on earth do they do that? For me is just uncomfortable and of no use but there are so many going on out there that I may be missing the point...
(a) They don't know how to use one, but they have it installed anyways because it came with the lens
(b) They do know how to use one, but forgot to switch it around
(c) They do know how to use one, but don't have time to switch it around
(d) They do know how to use one, but know enough when to and not to use one (that's me)
Just because you CAN use a lens hood doesn't mean you NEED to use it in all situations. Many situations it will make no discernible difference, but in many situations it will make a big difference, but you just can't tell before you take the shot
For me, most modern lens hoods are just plain poorly implemented, that's one of the (minor) reasons I don't have much modern glass. I prefer screw-in reversible hoods, like on my 75/2.5 Summarit-M as well as the classic Nikkor built-in slide-out hoods or on my Leica Telyts - out of the way during storage and easily implemented when needed.