Calm down Souf its not what you think...
I did that conservation of momentum/energy experiment at my household with a golf ball and a pretty lumpy basketball. (Of course upon examining the golf ball it also appeared to be in pretty rough shape.) Holding the golf ball from a height of 5 feet, i saw that it bounced up to a height of nearly 3 feet, and dropping the basketball from that same height it rebounded 1 foot. After dropping them together from 5 feet repeatedly my data is as shown.
1) Its much harder to drop the two balls perfectly on top of each other than Mr. Fullerton made it look.
2) After multiple failed attempts to shoot the ball straight up i noticed that the golf ball was still flying off and landing approximately 12 feet away.
3) When i finally did it right, the ball peaked at around 9 feet.
All in all not a bad experiment, seeing as nothing was broken during its testing. I know that there's some physics stuff that goes along with this, but for now I just want to say it was cool and that i do understand how and why it happens.