It's really quite simple. Money. Developer time costs far more money than hardware. If you really need "high perforance," then use C. But, if you want to get a product out the door in a much more timely manner that is still correct, robust, and maintable, then you can do so with Perl -- and other similar scripting languages, but Perl has the CPAN.

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)