What's with the cups?

I started playing warhammer 40k about 2 years ago. I really enjoy this game, and have pretty much obsessed over it non-stop. We have a great group of gamers here, and they have taught me a lot. One of the first things that I had to learn was that your dice have to match your army or else they wont role good for you. Well I had bought my dice to match my army but, every time I played a game my dice would crap out on me. I then tried buying new dice, and that didn't help ether. I then started to think about my childhood and how my step-mom use to play yahtzee with that damn annoying red cup. She use to role a yahtzee all the time, so I figured why not give it a try. I work at a prison and we have a craft shop there were offenders who have stayed out of trouble can make things like leather belts to sell. I saw a leather drink cozy with a team logo on the side that an offender had made and I thought of added a lid on it, and val la the dice cup was born. I started rolling like a champ and haven't looked back since. The funny thing is that if I have to make a leadership test, I role the dice with my hands because of how terrible I role when I touch the dice.