Yeah, at $30 I'm not as upset. I still predict they'll be annoying, but if you bring your own cat5e cable too (vs. plugging into an existing cable), it's less likely it will be left behind. (I'll probably order one for my 2011 MBA anyway).

Keys/wallet/etc. remain in pockets when not in use, though -- so they're a LOT less likely to be abandoned than something which is small, connected to another long cable, etc.