>>63917803
Capitalism + the Internet.
Meatspace square footage is expensive to own and maintain, and limits the clientele to "anyone close enough to drive who knows about and wants to buy things the store sells". That's fine when you're talking about things with broad appeal and/or dense urban areas, but get too niche and there's a solid chance you simply won't have enough clients to make ends meet. Much simpler (and cheaper) to just own a warehouse and website and advertise on third-party forums that already self-select for people who would want to buy your product.