It isn't. There are two sides to Bintan: Bintan Resorts (Lagoi), the northern bit, is a Singaporean colony with facilities and prices to match, meaning there's no cheap accommodation. The "real" Bintan is the rest of the island, but most visitors go there for cheap beer and whorehouses, and you'll need to get an advance visa as main port Tanjung Pinang doesn't have visa-on-arrival facilities. (The Resort's port does.)