Land was being mass produced in the first half the 17th century. My guess is that people couldn't imagine running out of land because you could keep reclaiming it from the sea, but they could imagine running out of tulip bulbs. Thus they undervalued land, and overvalued tulips.
Similarly, during the .com bubble, people couldn't imagine a slightly improved search engine would be worth anything, but an online grocery store seemed like a gold mine.
