I bought my Costco membership so I could buy a hearing aid, so call the cost of the hearing aid $855 if you must. That's still more than $2000 in savings. The

I bought my Costco membership so I could buy a hearing aid, so call the cost of the hearing aid $855 if you must. That's still more than $2000 in savings. The free hearing test was performed before paying for the membership. Sure, salary is an incomplete proxy. Each also requires a bit of real estate, support staff, and equipment. Both my optometrist and the Costco vision center have a larger space than the Costco hearing center. The Costco hearing aid area typically has one assistant (not an audiologist) working. The optometrist also has at least one assistant (optician). I chose eye exams and glasses because it is probably an experience that more people can relate to. Proctologists are MDs ($389,700/yr), have more complex facilities and equipment, need more support staff (reception, nurses, aenesthesiologist), have more complex sanitary needs (proctologists perform surgery), and tend not to send patients home with custom-fit devices. As for inventory - it very well could be that an optometrist does not pay for it up front.