A flame symbol on first and fifth reel enables 15 free spins. Wicked Winnings II - Enables bonus features such as re-spin if the reel has a stack full of devils. Wicked Winnings I - The original that possibly redefined what you can win off a penny/nickel slot.
People seem to like the possibility of winning big, I've been two to nearby tribal casinos recently and to this day they kept all 4 on their floor. Looking at the volatility of the Buffalo slots, I am reminded of another popular Aristocrat slot, Wicked Winnings.