This is pretty solid, but it could be funnier. Here's my rundown:
"These are no ordinary beans, though they may look like ordinary beans, though they are in fact identical in every meaningful sense to ordinary beans." Sometimes immediately contradicting yourself works, and sometimes it doesn't. Here, it does. Kudos.
"See that. I now have your nose. That is the power of the beans my friend." Cracked me up. You might even throw in one or two more generic, stupid magic tricks for good measure. "Watch as I make a quarter appear behind your ear!" "Watch as I pull a ridiculously long handkerchief from my sleeve!"
The George Foreman quote. That was my biggest laugh of the article.
WHAT DOESN'T WORK:
Having three sections before "Got your nose." They're too similar! It's not exactly long enough to get bored, but it's long enough to get worried that this isn't going anywhere.
"Fucking moron" and "douchebag." These are not words that a turn-of-the-century mustachioed villain would use. And since you have a prominent picture of the aforementioned villain, I want to see more speech appropriate to him.
The disclaimer at the end. It's not terrible... there are just stronger ways to end this, I think.
Identifying the reader as "Jack." This works a lot better if the reader is... well, me. Or whoever else is reading this.
I really like the idea of a "Why?" article that exists solely to bilk me out of my family's only cow. I also really like the idea that the article is written by such an incredibly anachronistic villain. My one suggestion: play up that anachronism a little. Have him say some phrases that haven't existed in the American lexicon in sixty years. You won't regret it.
Prose and formatting:
This is the weakest part of the article. The section breaks don't break the article into sections. Obviously, that's intentional, but I still think having an identifiable theme for each section would help, not hurt. Also, the usage is a little sloppy. Take the first sentences after the TOC: "I have a proposition for you my good friend! One you simply cannot afford to miss!" Well, I'd think this villain would be hyperliterate, and would probably phrase that, "I have a proposition for you, my good friend - one you simply cannot afford to miss!" It's subtle, but that extra comma, and fixing the sentence fragment by changing the period to a dash, really give the whole piece more credibility. Other examples abound.
The first picture is a 10: that really sets the tone of the piece. The second picture is a 5: it doesn't do much for me. Maybe put some glitter on it? Replace it with an emaciated cow? Anyway, 7.5 is your average.
Averaged (by the way, trying to average that with the Pee template nearly caused Uncyclopedia to explode). I'm really going back and forth on whether having a beanstalk spring from these beans would make the joke funnier or kill it entirely. Well, probably kill it. Okay, never mind.
Tighten a few bolts, turn a few screws, and this one may well be good to go. Cheers!