I lived in a house next to the Wabash river for 50 years and the finished basement never flooded. We did have a working sump pump. Insurance premiums on our house was figured on the replacement estimate for the house, including the basement. Basements during construction are space for utilities, convenient access to plumbing and electrical wiring, and HVAC installation. I would prefer to work in a basement and not a crawl space. A finished basement may add 30-40% to the price of a house compared to one on a crawl or slab. So I suppose it is up to the person what they want and how much they think it's worth to them.