I'm guessing in 99% of cases this information is either ignored or dumped into a database where a surveillance dragnet will lightly touch every record regularly looking for specific matches.
But in the remaining 1% it will be abused to skirt around someone's human rights.
And maybe they're hoping to catch some really dumb terrorists that write down the "Death to America" forum on that list.
I do find it interesting that the form is not compatible with anonymous posting like 4chan.