When you do all of the math, they are not that much more expensive than other LEDs.
Consider this:
To make a small multi-color LED tree you would need:
4 strings of LEDS (red, blue, green, and white) + a DMX SSR4 or 1/4 of a Lynx Express to control them
-vs-
a single strand of SS pixels, an SSC, and 1/16th of a hub
In addition, the SS tree can be any color plus do other interesting color effects.
To make a huge display, OK that is cost prohibitive, but you can add a little each year...
RM