Shoe Protectors Camera, Hot Shoe Adaptor, External Flash... Is It Necessary?

Camera, hot shoe adaptor, external flash... is it necessary? - shoe protectors

I have a Canon Rebel XTi and 580EX II, I use a shoe adapter and a surge protector between my camera and external flash. External flash and locks into the adapter but the adapter into the device to lock. It seems a little heavy, and I fear it will slip. Is it really necessary to have the card?