Well it does not matter whether the average Joe knows about Perl, but it does matter whether the average nontechnical manager has ever heard of it. If they always hear about Java, but have never heard of Perl, how do you think they'll react if one guy suggests implementing something in Java and the other in Perl?
I may not be paining my flat myself, but if the mister painter asks me whether I want him to use brand A or B and I've heard a lot good about A (and have no way of telling whether it's true or not) and never heard of B, I'll probably want A. And even more likely if he tells me B is much cheaper.
Always code as if the guy who ends up maintaining your code will be a violent psychopath who knows where you live.
-- Rick Osborne