It's pretty simple actually,
A protein shake before the gym, if no meal has been consumed, is a great idea.
A protein shake after the gym, is a great idea.
A meal before the gym, then a protein shake after, is an excellent idea.
Basically, it doesn't matter what source you use for your pre-workout protein, as long as there is a pre-workout protein, as fueling your body with protein pre-workout is extremely beneficial.