You should bill them for your time.

Maybe they have another position that will be opening soon (Like if someone's being fired or quitting) so they wanted your application on file

why would you travel 2hrs for a job interview..

Probably by someone who go there in 10 minutes and filled out the questionnaires in five minutes. Time is money, slowpoke!

Sounds like they might plan on contacting you if they get an opening for that post again.

A hiring agency can gather applications, even if the position has been filled. Some collect data which goes up against a position rating score, compiled to strategic assessment before ever being reviewed by any human interface. Systematically, the score is levied to tailor primary candidates for future interests within the core, or even supportive roles within the companies structure to fulfill the foundation of its operations and long-lasting objectives. Also known as, "Fools be collecting applications." Did you just read all that gibberish?