I think you maybe misunderstand the point of this web site.
The designer has no interest in selling all or even most of the logos at the sort of market rate they could actually command. The website is much more useful as a portfolio/marketing tool than as an actual logo store. What the designer wants is for the price to rise high enough to prove that he can sell logos and to set expectations for clients who want custom work, while also guaranteeing that most of the logos go unsold thus keeping his portfolio active and engaging.
If the price went down with each logo sold, he might never even get that first sale, and if he did, there would eventually be a snowball effect which would lead to everything selling out, and his no longer having such a neat attention-getting portfolio.
The designer has no interest in selling all or even most of the logos at the sort of market rate they could actually command. The website is much more useful as a portfolio/marketing tool than as an actual logo store. What the designer wants is for the price to rise high enough to prove that he can sell logos and to set expectations for clients who want custom work, while also guaranteeing that most of the logos go unsold thus keeping his portfolio active and engaging.
If the price went down with each logo sold, he might never even get that first sale, and if he did, there would eventually be a snowball effect which would lead to everything selling out, and his no longer having such a neat attention-getting portfolio.