1stdibs CEO David Rosenblatt explains how his company, a marketplace for rare luxury products, made the transition from an advertising to e-commerce. Unlike other executives in the commerce space, Rosenblatt isn't worried about Amazon competing with him directly because 1stdibs' sellers aren't comfortable selling their expensive goods alongside lower-priced brands. Rosenblatt also talks about the growing importance of VR and AR for his industry and how his former company — the online advertising pioneer DoubleClick — survived the dot-com crash and got acquired by Google.