Not all decisions in a business are based on technical merit. There is also cost (developer time), ease of maintainability, and the number of developers on-staff that can maintain it. There are also other business/management issues that you may be unaware of.

Though don't get me wrong, a lot of decisions are made in companies based on little or inaccurate information, or just because the Big Boss thinks it's the Next Big Thing, but just be aware that Perl isn't always the best solution for the task, and while it seems that in this case it can probably do the job very nicely, there may be other (probably business) reasons they chose to go with what they did.

If you're involved in the early stages of a project, and you think Perl is the best choice for it, by all means express your opinion and back it up. Perhaps they just haven't heard of Perl being used in these types of things. You'd get bonus points for having a working prototype in an hour. Rapid development = major $$$ savings.