Buying a PCIe drive in the first place is already pretty toilet money.
Your right about people compromising on specification specifically to watercool. From a PURE price/performance perspective it doesn't make a great deal of sense. Very few people (particularly on hardware forums) are going to be of that opinion though. Impulsive, excited and at times just plain irrational thinking are always going to come into play. The PC hobby is probably one of the tamest for shear overkill and compromise, you only have to look at people who get enthusiastic about cars, motorbikes, houses, fishing, shooting... to realize there are FAR more irrational things to do with your money.
JR