Having said that I suppose some arts which are based less on striking or kicking might just recommend using an elastic support without the hard plastic cup as this might nip a little.
Shorinji kempo is both hard and soft style so hitting and kicking is pre-requisite so I really need the cup.
I've always worn knee pads too (volley ball ones are more than adequate) and lately have taken to wearing small ones for my elbows too).
I prefer the comfort to the body 'conditioning' approach...
Am I getting old?