I assume because they needed to grab everyone they could in one shot, since they are outside of the U.S., and it can turn out that one or more of them are in fact guilty. Otherwise, they can just disappear and you'll never get the chance again.

This actually makes sense if you consider that these laws are aimed at the mafia, and that there is no penalty to the U.S. government for being wrong.

EDIT: I find it interesting how everyone always jumps to the "OMG EVIL" conclusion with these things. From what I've seen, American law enforcement can be overzealous, heavy-handed, and cause a lot of collateral damage, but they are rarely "evil."

"wrong" =/= "evil"

Throw charges at everyone and see what sticks? Plus, they can try to leverage them to plea against their main targets / give evidence against them.

Intimidation. I bet they also want to "make an example" of megaupload and any other similar company.

That's pretty scary. I used to work for a company that had similarities of MegaUpload. It was all above board; I was paid a salary, didn't have any ownership in the company, and we obeyed the law. To think I could have been arrested for what I saw as a day-job is not cool.

They're probably listed as officers of the corporations.

Fear.