Do the ends justify the means?

This post is not my usual sort of thing. It is a reaction to the article in this week's Jewish Star, "Obscene billboard still in plain sight on Rockaway Turnpike" by Michael Orbach. I've seen the billboard in question while driving past. I actually would call it a sign because it is posted over the building of the "gentlemen's club" it is meant to advertise. The woman who is pictured in this sign is very provocatively clad. Is this something I find personally offensive? Yes. But I find quite a number of public displays personally offensive. For example, I find many of the images flashed on the TV screen in my gym's machine room equally offensive with women clad just about the same way dancing or otherwise displaying themselves on what I assume is the MTV channel. I alsofind some of the lyrics of the music pumped over the speakers offensive. And this is the gym that caters to the frum women in the area!
But what I consider inappropriate, morally degenerate, exploitive of women, etc. is likely not obscene in a legal sense. Defining obscenity is actually not so simple. In the course of teaching rhetoric, I've read some arguments on just that question with regard to curtailing free speech. While those opposed argue on the grounds of the proximity of a family neighborhood, I don't know if that will hold, as such a legal consideration should have prevented such an establishment from being set up in the first place. (BTW I noticed on camp visiting day that there was more than one such place in the country just down the road from some Hasidic bungalow communities, though their signs didn't show any flesh.)

And here we come to the question of the means proposed to bring about the end of the sign:
"If the billboard is not removed, Davis said, she would consider other ways to persuade the owner to do so, such as videotaping patrons entering the club and
posting the videos on Youtube."

I quoted that directly so that I would not in any way distort what was proposed. There is something very dishonorable about that proposal in my view, and just the picture it conjures up of someone lying in wait outside such a seedy place to catch people on video in order to attempt to publicly humiliate them does not sit right with me. Again, I want to emphasize that I do not approve of this club, its ad, or its devaluation of women and moral values. But the people protesting now didn't mind the club's presence only the stark reminder of it in the sign.