1. Facebook is ultimately trying to get money from advertisers. Advertisers probably don't want people to be able to share negative feelings about products on Facebook, so not including the option to dislike pages means that Facebook facilitates positive press for those wishing to advertise.
2. They want people to stay on their website more. Having a status, picture, or comment of the user being liked is generally a positive experience, which would tend to make people use the site more. On the other had, allowing people to dislike things could cause users to feel rejected and have bad feelings associated with Facebook.
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Fame is but a slow decay.
-Theodore Tilton
There should be an "acknowledge" button.
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Willis, it seems like every other time you post, I need to look up a word that's in the OED or Urban Dictionary but not both.
-Mimir
I'd say originally, when the idea was first brought up a few years ago, it was because of reason #2. Now it is by far more #1, but #2 still having a strong influence.
I also think that disliking things could really create some BAD cyber bullying, which is a problem that many people are trying to prevent.
...I have a bit of a personal connection to this issue really. I know someone who was deeply affected by bullying on Facebook and unfortunately took his own life because of it...
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Well, there is a new accent of n00b language. It's called: Vet LUEser goes Foreign!-MegaSpy22
Those must be the pants of the gods!-Digitalpython