The large supply of salt water creates demand for ocean front property.
LOL True, but that’s not the same. That’s demand for land, not water.
A large supply of snakes might create demand for snake repellent, poisons, hoes, maybe even mongooses (mongeese?) but it won’t create much demand for snakes. It’ll create some, the price of snake skin boots might fall generating a small increase in demand.
But generally, it can’t be said that supply always creates demand. The market seeks to balance supply and demand through market price.
In the case of salt water, that equibrium price is $0. And the water remains in the ocean unharvested.