Surprise, people enjoy websites that make them laugh.
lolcats and failblog require absolutely no intellectual investment at all. It's like eating a nice steak...it triggers that part of your brain that goes "this is good", but doesn't actually require you to do anything.
This does, however, bring up another point...are there any other animals that experience humor?
He didn't found LOLcats, which isn't a company and wasn't started by this man / icanhascheesburger.com, or by The Times (who also publish a LolPets section), but by 4Chan.
Kudos to him for taking something niche and making it accessible to the mainsteam though.
I want to honestly send this guy a $100. I can't count the number of times I've cried due to laughter from reading any one of these sites. The content is amazing.
Heck, I (and my friend) was doing pigeon English comedy articles AND hybrid catheads (where the head is half of 2 cat's faces with eyes bulging intermittently), in 1997!
http://www.time.com/time/magazine/article/0,9171,1916286-1,0...