What kind of competitive advantage do you have compared to other similar companies (e.g. Hubble [1])? Is contact lenses just a race to the bottom in terms of pricing? Other than cost, are there any other elements that differentiate you? [1] https://www.hubblecontacts.com/
This is just ecommerce automation in a niche vertical. Here, they draw in buyers, they stock inventory, and they fulfill.
Maybe he's able to upgrade and use better software to get rid of 15% of "waste" or maybe he's just eating into his margins and it's too early yet for him to realize, either way he's marketing it as a "savings" passed on to the consumer.
Which doesn't mean it's not interesting. If he can prove that his software mix really is contributing to lowering costs and if the niche doesn't sustain/support the business then most likely he ends up finding another niche or selling access to his software tools to help other ecommerce businesses thrive. E.g. sell shovels in a gold rush.