Why do manufacturers of goods often not work directly with consumers, but sell wholesale?

In 2018, I found the shirt of my dreams. I decided to buy more of the same, started searching by manufacturer on marketplaces – nothing, by the picture on the manufacturer’s website – nothing. I went around the stores – barely found another one. And then in another region – three more.

I wrote to the manufacturer – they said that they only sell wholesale and to businesses. There are no marketplaces. I wrote to the manufacturer again, and they met me halfway, sold six shirts from a wholesale base in my city as an exception.

Now manufacturers are trying to sell their products themselves and work with consumers directly, but why don’t all of them do this? Is it really profitable for them to lose money due to the same commission on Wildberries or Ozon? Or just sell goods to obscure stores where the buyer cannot find their products? I tried to find that very shirt offline, it was very difficult. Although the products are good.

How to motivate companies to sell goods directly to customers? Can an ordinary consumer influence this? Why don’t all companies work with this direct sales model? Or does it depend on the niche?