First - check your maths.
1 litre/min is 60 litres/hr, so 1500 litres/hr seems somewhat of an overkill... by a factor of 25.
The price is a reflection (in part) of the market it is targeted towards - gamers. It will also be built for reliability over extended periods of operation. Gamers tend to lose track of time.
Unfortunately, I don't really know where to point you.