You would have to have been in Brooklyn Heights for over five years to remember when the last tenant, Starbucks, moved out of 112 Montague Street (photo) to a smaller space a block away. Since then, apart from being used as storage space for Lassen & Hennigs next door, the space has lain fallow. While there are no similar long-term vacancies on Montague (well; there’s the Bossert, which is not quite vacant because of a few holdover tenants, but that’s another story), there are others not far away.Why? Greedy landlords? Bricks-and-mortar retail is dying because …