not a teen necessarily, but someone with more time on their hands. i feel it all comes down to why you use a computer and how you like to use it.
it's like cars. the vast overwhelming majority of car buyers today (and probably since the 60's) just want a vehicle that works for them. they have certain wants, such as performance, economy, room, etc. and they just want to buy a car that fits their bill and drive off. they don't want to have to futz with it -at all-. if they could get away with avoiding oil changes, wiper blades and new tires, they'd love it.
there are a few who want to customize a few things, but not many. these few are usually content to change out the stereo and that's it. fewer still add things like custom interior items - steering wheel cover, floormats - minor stuff.. simple.
then you start to enter the realm of the 'enthusiast.' there are even -fewer- of these. still enough to base industries on, but compared to the total number of car owners, an incredibly tiny number. power amps and giant subwoofers. custom seats, like a nice recaro or sparco. custom tires. custom body paint.
then finally, the deep end, where people are re-doing the power train, suspension, etc.. the hardware.
it's the same for computers. exactly the same. starting with people who add on things like winamp to replace wmp, all the way down to those who pull out windows and replace it with linux.
now.. how many people do you know in their teens who have an aftermarket stereo in their car? people in their 20's? 30's? the number keeps getting smaller. of course, there are still people in their 60's and 70's pulling out engines and reworking suspensions, but the numbers of customizers and the level of customization they're into starts out small and drops with age.
as far as it applies to freeware, the general assumption of the mass of computer users is that freeware will involve more fiddling and time. for some, this is part of the draw of it. they enjoy the fiddling

for many though, they're willing to pay so it does what they want, right off the showroom floor.