You got a job? Would you like to work a day unpaid?
While I like to save a buck as much as the next person, stealing copyrighted materials (i.e. plans) is just plain wrong. And if you're just thinking "It's only $40.00, what's the big deal?"; the price for plans are based on 1] how many hours it took to draw up said plans, 2]What it took to build, revise, test/ prove out said plans, 3] How many copies they think they can sell.
Every step along the way costs money, and there's no guarantee for success. So, if you were in their position,
WHY should they willingly allow plans to just be copied for free?
This is a legitimate question; how would you feel if someone was asking for the fruits of your labor for free? Not because they couldn't afford it; because they were too cheap (and felt your labors weren't worth the asking price).
I can't tell you what a certain set of plans are worth; I refuse to even try. All i do know, is that openly asking for copies of them is technically illegal.
Here's the basic question; if you were the designer, how would you feel about people trying to bypass your copyright?