Because the initial price would be steep. Let's say you spend $70 dollars on shoes and they last 2 years, so that's $350 for 10 years. It would be hard to design a single pair of shoes, especially at the beginning, at lasts 10 years. The goal would be to replace that pair after 5 years.

No one would pay $350 for a pair of shoes from an unknown company, but if I'd offer them for $3/month it's a different story.