That was a bug. Every new site experience issues at the beginning. and nobody is perfect. Even primedice had security issues so they lost $1.5M worth bitcoins to a hacker.
Now, don't you dare try to tell me that more than 2% of casinos have a ridiculously severe bug like that within their opening stages. When you're dealing with money - especially that which can be won or lost within
seconds you have to ensure everything is smooth. If you didn't even test to see that you could make negative bets then there is a serious problem on your end.
And the Hufflepuff situation is completely different. Don't make a crappy comparison: Hufflepuff gained the server seeds while on your end you allowed negative bets with a small bankroll unsuitable for the running of a casino.