And if you do pay the big bucks to a publisher for access to a scientific paper, there's no assurance that you'll be able to read it, unless you've spent your life learning to decipher them.
I know that this is a real shock to you humanities majors, but science is hard. And yes, for the record, I do have degrees in both [physics and philosophy, or will as of this May — and the physics was by far the harder of the two].
Here's another shocker. If you think the papers are hard to read, you should see the amount of work that went into processing the data until it's ready to be written up in an academic journal. Ol' Tom Edison wasn't joking when he said its "1% inspiration and 99% perspiration." If you think seeing the raw data is going to magically make everything clear, well, I'm sorry, the real world just doesn't work that way. Finally, if you think professional scientists are going to trust random data they downloaded off the web of unknown provenance, well, I'm sorry but that isn't going to happen either. I spend enough time fixing my own problems; I certainly don't have time to waste fixing other peoples' data for them.
-JS