That's quite an exaggeration. They are standing far away from the ceremony.
EDIT: To clarify, I don't mean to defend them. I just think what they do is appalling enough on its own, without stretching the facts.
The raft of state legislation in 2007/2008 setting up perimeters (300 - 500 feet, depending on the state) was in direct response to the stepped-up funeral protests of 2006 which were in extremely close, personal proximity to the mourners.
Now, they are 300-500 feet away, but only due to specific state laws.
Anonymous uses free speech to attack Phelps for being an asshole.
And you use free speech to attack Anonymous for attacking Phelps.
How many iterations should we take this?
EDIT: It should also be noted that in the United States (where Phelps is based), restrictions on "hate speech" have not fared well in the courts, as they are usually seen as an unconstitutional restriction on free speech.
http://en.wikipedia.org/wiki/Hate_speech#United_States
Looks like the Supreme Court is due to rule on a case involving Phelps that may settle some of these questions from a legal perspective:
Any boundary will be imperfect, but that does not mean we don't set boundaries.
Who decides what's too much? I do. And you do too. And we keep trying to get better at setting intelligent and fair boundaries.
--Justice Potter Stewart, concurring opinion in Jacobellis v. Ohio 378 U.S. 184 (1964), regarding possible obscenity in The Lovers.
Let's be clear here. Stalking, harassment, and invasion of privacy--those all may or may not be legitimate things WBC can be rightly accused of. If the WBC is in the wrong, they're in the wrong for disrupting people's funerals by shouting at the top of their lungs, not for the specific things they happen to say in the process. "Hate speech" is a bullshit political euphemism, and the right to march down the street or stand on a street corner to share your views is the essence of free speech. It doesn't matter whether you're the WBC, the Ku Klux Klan, or Lyndon LaRouche.