Saturday night on a Shenzhen street corner, a young guitarist dressed in Johnny Cash black strums away, singing melodies. His open guitar case has a laminated QR reader, propped up, welcoming digital tips from passersby. China’s expeditious adoption of fintech is generating profits not only for startups, but also the companies investing in them. Sitting in the headquarters of FinPlus, a fintech venture capital firm and accelerator, its CEO, Mosso Lau, said, “There are very many...