In E-card, they say that Kaiji has the possibility to win up towards 100 million yen. However, if you actually do the math, you'll find it's slightly more than that. 1 mm = 100 thousand yen. If he bets the max amount for each round note 30 mm and never loses once, he would win 18 million from all the Emperor rounds note 100k*30*6=18 mil, and the money received from winning all of the Slave rounds would be 5 times that amount note 18 mil*5=90 mil. Add up the total sum and what do you get? 108 million yen.
In the One Poker arc due to the low chances of timing it right, as well as the assumedly impossible task of grabbing onto it when falling, there is seemingly no reason for the web meant to save you from dying after losing, outside of it acting as a Hope Spot. However, Kazuya needed a guaranteed safety precaution in case he ever ended up betting his red life and losing, and due to the nature of Mother Sophie being designed to be fair, he needed to hide a secret way to deactivate it on both sides, while keeping the method as hidden away as possible. As a result, he invented the net, with the sole purpose of justifying the existence of the button made to deactivate the penalty.
