The beauty of bulk bins is that the item costs the same whether you buy a pound or an ounce. It makes sense to buy the ingredients you use all the time in larger bulk, but for the things you buy only occasionally — like spices for a new cookie recipe or nuts for Christmas dinner — just buy what you need.
I find that I'm particularly guilty of picking up a whole cup of a special spice when I really only need a few teaspoons for my recipe. It feels silly to buy such a small amount, but the extra inevitably ends up scrunched in the very back of my spice drawer. Specialty flours, fancy grains, or really, any ingredient that I'm buying for one specific recipe: these all fall prey to my tendency to bulk up on bulk items.
This is a tip I need to repeat to myself every time I go to the grocery store in the coming weeks. Buy what you need. And it's ok to buy less.