Buying in bulk offers obvious savings by cutting out the cost of advertisements and fancy packaging. A great article put out by Whole Foods Magazine, stated that purchasing in bulk can save 89% compared to their packaged equivalents. [Don't believe this? Price out the cost of replacing spices in bulk vs. pre-packaged spices]. Additionally, the companies who manufacture bulk products can reduce expenses by 54% on material delivery costs.
Most importantly, when people purchase a desired quantity of a product, they tend to use it. This equates into less overall food waste, which is an issue we struggle with as a nation (40% of food in the U.S. goes uneaten).