Buying in bulk is:
- practical and efficient, you can save a lot of time at the store.
- possibly healthier, because storage condition can be optimised, which is particularly important for fatty foods. Especially those containing easily damageable polyunsaturated fatty acids. Retailers often do a terrible job with storage. Nuts and olive oil (EVOO) should be stored cool (8-10°C) and not be exposed to light, for instance, but I have never seen a store do this.
- ecological, because you need less packaging material.
- cheaper, since you get discounts.