I'll bet you use wifi in public places.
I'll bet you type your password into your computer in public places where anyone with a decent cell phone can steal your password by simply taking a video.
Let see I sit down at random at a table in a pubic wifi place and there happen to be a person who know I am running truecrypt or think I might be doing so with one hell of a good camera phone to be able to get video clear enough to see my fat figures keying in my long password as I lean over the keyboard.
All without me taking note?????
Oh and then they somehow get a hold of my computer?
Sorry but even if bad guys do all this they still do not have access to my passwords because my passwords file is protected by being inside a truecrypt volume on the encrypted drive and I would have little reason to mount that volume in a public place!!!!!!!!!!!!
Oh it does not share the same pass phase with the WDE so the bad guys with their camera phones are still out of luck.........
Your example also happen to be way more of a risk model then I am likely to ever face in the real universe.
As far as using public wifi so what?
If I do so for anything more serous then postings on this website I either had a SSL connection and I also check the cert or I used a vpn or both.