They're trying to make a point, after all.
In fact, the point isn't to restrict access to knowledge—it's to emphasize what they believe to be the likely consequences of the proposed legislation. (As such, with a little creativity, you can still get at Wikipedia content in several different ways.)
Speaking of the bills, they're written with the kind of bombastic language that only serves to polarize and mislead people. For example,
in SOPA, there's a section called "TRAFFICKING IN INHERENTLY DANGEROUS GOODS OR SERVICES." It's actually about counterfeiting trademarks, labels and certifications. While that
can lead to dangerous situations, the fact that it
usually doesn't makes this a clear misuse of the word "inherently". Similarly, another section is called "IMMUNITY FOR TAKING VOLUNTARY ACTION AGAINST SITES THAT ENDANGER PUBLIC HEALTH." That's about the sale of prescription drugs without a prescription, and the misbranding or adulteration of drugs. There's not a word about requiring anyone to prove that such a site actually endangered the health of the public (or any member thereof). Instead, they just define the term "Internet site that endangers the public health" in a way that assumes that these things
necessarily endanger the public. Again, they
could sometimes endanger the public, but no such uncertainty is expressed in the text of the bill. It goes far beyond reasonable sanctions for potentially harmful behaviour, and tries to justify its excesses through hyperbole.
To detractors, this kind of linguistic imprecision (or outright malice) reinforces the draconian nature of the bills, and diminishes the credibility of the bill's legislative sponsors. To supporters, it gives the appearance of validity and urgency to their concerns.
Incidentally, this is a good example of why lawyering the FIRST rules is good practice for the real world. By critically analyzing FIRST's errors, you practice for the day when you need to critically analyze legislators' errors (and deliberate trickery). FIRST's errors are annoying, accidental and have relatively minor consequences. Real-world problems aren't often so trivial.