Probably because they did not have enough time to develop it, combined with bad management. If the Dutch would have kept the New Netherlands, I am fairly sure they would plant tobacco and make something out of it, wether it would be the WIC, or the Estate-General.You can grow tobacco in New York and Connecticut OTL, and this was exported during the period. Makes you wonder why the Dutch never considered pushing it more aggressively; I could imagine a lot of Germans who would become indentured servants, like in Virginia...