There were no backups.
The victims' offer of a $1,000 bounty for the return of the laptop is presumably based on the assumed value of the stolen hardware to the thief. If what they claim about the data is true, it's a small fraction of the true value, but still a substantial sum to them (being poor research scientists) and to some crack-head opportunist.
I urge all of you reading this to stop whatever you're doing for a moment and consider what will happen when your IT systems are stolen, go up in flames, get flooded out, are dropped on the concrete floor, get hit by static or struck by lightning, fail spectacularly in a strangely beautiful shower of sparks, are run over by a Chieftan tank manned by an irate neighbor high on booze, or get eaten by little green men from the Tharduriz galaxy over here on a secret fact-finding mission and just feeling a little bit peckish.
Imagine for one horrible second that it's true. It's happened. The bits n bytes are even now being consumed by alien digestive juices. OK, what have you just lost? Think about it. Picture yourself as the unfortunate victim.
Now tell me you "don't have the time" to take backups or "need to buy some more CDs".
The Tharduriz scouts are right behind you.
PS Make it a new year's resolution to back up your data if you like. Worst case you'll lose a whole year's data, still terrible, tragic maybe but hopefully not completely disastrous. Oh and by the way, do check that yourbackups are sound by testing your ability to restore the data - NOT over the top of the live drive (a failure in that case would be doubly tragic).