Totally agree with this, but PhotonStorm doesn’t. Basically, if you make the bounding box not include the transparent parts of the image, what is to stop someone from making non square or circle shape in arcade physics?
What I’m saying is: I feel your pain. The only good way to make walls in phaser, even invisible ones, is to use the phaser editor, because without it you just spend all your time placing the walls in the right position, refreshing until you get it right.