The burglar knew his gun was fake, but used it as a threat towards the family, bluffing that they would believe it was real and cooperate. They called his bluff.
I examined many of those types of guns and it is very hard to tell the difference, even when you are setting in a lab examining it. That is much, more time and far less stressful than having someone waving it in your face, making threats to shoot you with it and trying to see if its real or not. He's acting like its real, making threats, ... well looks like a duck, talks like a duck.. probably is a duck.. his bad that it wasn't real.
It's in the news all over these days, with home invasions. These criminals, for what ever reasons are looking for homes with people in them. They do this so they can force, threaten, intimidate the homeowners into giving them the money,jewelry etc. instead of a burglar waiting for no one to be home, and looking for it themselves.
Home invaders can get in and out much quicker, get their thrills out of having control and power over other people, and often if there is a female occupant, take the time to assault them.
With Juries and the CSI effect going on, I get tired of testifying in robbery cases, where the female/male victim are beat up, threatened, robbed, do a composite, identify the guy from a lineup, testifies herself in trial putting up with defense attn innuendo's, only to have a jury say "she could have been mistaken", there's no DNA.."What???"(You don't get DNA or Fingerprints on many of these type cases.. the bad guys watch CSI too!!) And let the guy loose with a not guilty, because there was an unrealistic reasonable doubt, with no evidence to support that doubt..BTW he had a rap sheet 3 pages long of robberies..
Economy is tough on a lot of people, when that guy made the choice to go as far as he did, to get easy money, I don't see him trying to rehabilitate himself and be an upstanding citizen.
The news media and law enforcement down here have let the criminals know, that they just might be robbing someone that is a better/faster shot than they are and the "would be victims" have thier support.