Have you seen eg. Germany's bond yields? They are negative. People love safe money parking, they don't want to take risks, manage investments, oversee companies, fiddle with product development, bet on innovation, think about market fit. So they do the next best thing, try to come up with minimal risk minimal profit financial products, and that's what these furniture/fridge/oven loans are.

Furthermore the shop pays some service fee to the loan provider, and thus they scrape by.