For reasons that should be obvious to everybody, it's illegal to park your vehicle directly in front of a fire hydrant. They're there for the protection of the public, and they're used in the event of a fire breaking out. If your car is in the way, the fire service theoretically can't access the hydrant to put out fires when they occur. In practice though, they'll find a way around that - as this rude driver found out to their cost.
As it would have been impossible to put the hosepipe under or over the car, that left the fire crew one option, and then took it. The thoughtless driver lost both of their back windows, and they probably got a little water damage into the bargain, too. Hopefully, when they came back and saw what had happened, they had the presence of mind to accept that they deserved it.