The kinetic energy of the mass of exhaust gas carries it along the exhaust pipe, and causes a pressure build up ahead of the mass of gas and a partial vacuum behind it. This principle is used in a tuned exhaust system.
Culligan - $2352 ($2053 w/o R/O unit) Culligan Gold Series (10), Good Water Machine. If I were to look at price only, I would go with either the cheaper Ecowater system w/R/O at $2698 or the Culligan system. At almost $4k, the Kinetico system seems greatly over priced.
A person can become a Culligan dealer in a particular geographical area. It requires a rather large investment. Prices for water softening systems will vary greatly depending on where you are located. Even then, since it is a direct sales type of company, you and your neighbor may buy the same identical system, and you will pay different prices.