my mouldy bread

I don't understand why the loaf of bread in Melbourne is so big! Before I can even finish it, it has mould all over it!! I wanted to make myself a peanut butter sandwich and saw my 6 pieces of bread with specks of mould growing on them! This is not the first time. I sort of expected it to be mouldy. Why don't they come up with 2 different sizes for people like me?