I decided I had to see this for myself. It looks like it's actually the travel insurance option, not the seat option, but close enough:

http://mikeash.com/tmp/screenshot_F1E1DACD-A595-455E-A5C1-E2...

And it wouldn't let me proceed until I chose something; leaving it at the default wasn't allowed. Very tricky.

Yes! In alphabetical order no less :)

That's worthy of a "Dark Pattern" annual award.