Just because there are places where Bitcoins could be spent does not mean people do use them.
Right. People are paying over $10 for something that they're not actually planning on ever using. That makes perfect sense. 
Remember the dot-com bubble? Remember e.g. InfoSpace? In March 2000 this stock reached a price $1,305 per share, but by April 2001 its price had crashed down to $22 a share.
According to your logic: People were paying over $1,305 per share for something that they're not actually planning on ever using. That makes perfect sense.
Or have a look at http://en.wikipedia.org/wiki/Tulip_mania.
Do you know how markets work? A thing is worth what someone else is willing to pay for it.