How many kinds of flour does one person need?

Today I was looking for some dried cranberries in my pantry and started looking at all the flour I had in there. I have cake flour, self-rising flour, whole wheat flour, un-bleached all-purpose flour, Gold Medal Harvest King (best for bread) flour and all-purpose flour. Why do I have all these kinds of flour?? I have been trying different recipes and have bought different kinds for different things. I used to just use all-purpose flour but now have a flour for every occasion...lol!