Why? Because I love learning stuff. Granted, Wikipedia is far from perfect, but nothing is. And for someone who likes trivia, it's awesome. In quiet moments I can click the "random article" feature repeatedly and learn all kinds of new stuff.
There are some things I'm sorry I've learned. Things I likely could go to my grave perfectly happy without knowing about.
The Hulaburger. In 1963 McDonalds (briefly) test marketed this bizarre creation, hoping it would sell with Catholics on Fridays. It consisted of a bun, cheese, ketchup, pickles, onions- and a thick slice of pineapple. It was invented by Chairman Ray Kroc, and I can only assume it got as far as it did because no one dared tell him it was insane.
The Ethel Merman Disco Album. In 1979 the legendary Ethel Merman felt the need to record some of her biggest Broadway hits as disco numbers.
The Bud Bowl scores. Of course I remember the odd "Bud Bowl" advertising campaign of the 1990's, featuring football playing beer bottles. It only aired during the SuperBowl, and some years was more exciting than the game itself. And I'm not surprised the ad campaign has a wiki page. But what frightens me is that someone actually tracked the final scores of each of Bud Bowl and put them in the article.
The ingredients in a McRib sandwich. I personally have never eaten a McRib, nor do I plan to. And if I ever had the slightest thought of such, learning that the faux-rib-shaped patty is made of pork shoulder and "restructured meat products such as tripe, heart,and stomach" would drive it out of my brain FAST.
As a child of the Atari 2600 age, I figured I'd played all of the titles for it. Even the shitty Atari Pac-Man, which I saved money for, raced home with, and was absolutely horrified to discover bore absolutely no fucking resemblance whatsoever to the arcade game. But I digress. Anyway, I was shocked to find out that there was actually an Atari game based on the rock group Journey.
I suppose nothing should surprise me where pornography is concerned, but learning that there's a porn flick based on the "Mario Brothers" video game franchise still did.
I am not a "high 5" person. I have never been, and will never be, a high-5 person. I have one patient who feels the need to give me high-5s multiple times at each appointment, and it drives me nuts. So I was especially horrified to learn that there is actually a national high-5 day.
These, and many less-strange facts (and a few more so) can all be found at Wikipedia. Expand your mind!