The probability of getting the longer losing streak is very low, but you may get the rare losing streak a few many times within a short time if you are unlucky. I have gotten 4-6 losing streak a few many times within 100 bets at 82.5% win chance. It doesn't make the game unfair or rigged. BCgame won't be able to gain such reputation if their dice game was unfair. You may verify the fairness of each bet if you want.
Same old stuff where gamblers lose their money and blame it all on the casino by coming up with all kinds of excuses. Personally, I have seen 26 losses in a row with a 49% winning percentage though they were all small bets luckily.
So many people like @Maasdamer invest their money without willing to lose it in the first place. Bad decisions!