It was a little difficult trying to find your stance on this issue because nearly your entire post was a quote from someone else, but...
This is why skeptics are unable to point to a single benefit to the world that came out of skepticism.
Here is an example. Christopher Columbus was, as one could describe, skeptical that the earth was flat. Thus he set out to prove it and discovered not only that the earth was round, but he discovered an entire continent (which lead to the discovery of a subsiquent other continent). Now some people may argue that having America around isn't a "benefit to the world" but you have to agree that his skepticism did discover something quite major. There, that took me 2 seconds to think of and I'm sure we could all come up with many other examples if it was worth spending any more time on.
There you go, you should return that book and remember... whenever you make absolute statements that are close ended claiming, no presupposing, that your statement is absolutely correct, be prepaired to be proven wrong.
Now let me propose a hypothetical to you all. And please don't just discount this because it opens you to a differing view point, but its important to expand your mind and put yourself in someone else's shoes. If a medium or person who talks to the dead turns out to be fake, lying or using trickery to "appear" to talk to the dead, what does that tell us about that individual's character. Now, I mean hypothetically if we had absolute proof! I'm talking through science we learn how to resurrect people and we ask one of these zombie-people if John Edwards (for example) or any other medium who had claimed to actually talked to him and he says "no". So now we have hypothetical proof, and thus we can insinuate that the individual in this story is either dilusional or realizes they themselves are fake. Now that supposed medium was out charging, any amount of money for this practice of which they know is a lie, and they know also how tough and scary it is to go through a recent loss of a loved one and use specifically that type of person as their primary target for this trickery. What kind of terrible, unconscionable act would this person be willingly committing on a weekly basis. Again, in this hypothetical we are saying if the person knowingly uses trickery to gain "something" from a grieving individual, what kind of person would ever do that?
Now lets take the hypothetical back a bit. Lets say the person did not have proof from a revived dead person and questioned them, but say this person is able to do the next thing. To achieve the same exact result (and sometimes better) by applying techniques of which they know are trickery and to gain almost the exact same effect from it. Why would that skeptic be wrong for being so outspoken on it?
The point is this, people like James Randi who are so outspoken against the paranormal, it doesn't matter if they are actually right or wrong, if they believe they are right they're being outspoken and trying to show the world about a farce for a good reason. They are trying to empower people to make up their own mind and don't believe what just one person speaks. How can you blame that person, whom feels they are correct, for trying to expose an injustice or listening to their conscience.