This makes a little more sense; gutting it for profit rather
   than blowing it up. They need to get money somehow and seizing
   ruins for-profit makes sense.

   Then again, there might have been no street-value on what was
   left over and then they blew that up. That's possible. But
   considering the photos were distributed by ISIS themselves, my
   gut tells me they're hiding something; *appearing* merciless is
   a VERY important image for them to project in this 21st century
   media war, and they know how to play the game very well.