Why are some things so expensive?

A 1/2 hp chiller runs over a $1000. The BTU's don't even rival a window
AC unit which runs under $100. Or, an office water cooler that runs $150.

Ballasts over $800.
Protein Skimmer for $250. Seems like a simple plastic device.

Sure they need to be rugidized for a salt environment, but Jeez! There
doesn't seem to be enough competition in these products. Or, am I
missing something?

--Kurt