That was a lot of paint he was hauling, even if those 5 gallon buckets weren't all full. Unsecured load inside the vehicle cabin is a safety issue that is not considered seriously enough, in my opinion. Same with suitcases, etc. Just think how much weight you're talking about, flying forward inside your vehicle in a collision. And it is not a matter of a careless driver, really - there is simply no reliable provision for securing any cargo in an SUV or minivan. I used to fly a lot in a small Cessna (not as a pilot, but as a passenger), and everything was always secured beneath a net, or tied down separately. I've often thought of putting some of those tracks & tie-downs in our minivan, but haven't so far. Now I'm thinking about it again. The guy could easily have been killed by being hit in the head with one of those buckets of paint. He may have been lucky that they busted open when they hit the back of the seat.