Not only is it not unreasonable, it's a subtle design touch that you would almost expect Apple to think of. Similar to how yanking the headphones out of an iPod or iPhone pauses the music.
I wouldn't even call it subtle. It's an obvious one. Since I got the thing, I've had to deal with it. The worst part is when I forget. I get into work, sit down, and plug the iPod in, and BAM, whatever I was listening to stops, thing start to run on my computer, asking me to update QuickTime, before I can cancel out,...
