I first thought that the traps can only be used once like when you capture a ghost you have to pick it up again and trow it again in order to use it again, but I see now you don;t have to.
BUT, I did notice something. The traps CAN be damaged if a ghost attacks it. It's rare, but it has happened to me and Ray said “He damaged the trap.”
How you fix it is you pick it up and throw it again.
Kind of interesting if you ask me.
I also noticed one last thing. You can put two ghosts in one trap. Me and Octallord did this while playing. We managed to get two ghosts into one trap and got score for both of them. It's really hard to do, but it is possible.
At the end me and him both said the “Two int he box, ready to go, we be fast and they be slow”