Those skis, boots and 12 pack of "tea" (beer or whatever), will become lethal projectiles in a crash or roll over!
I have seen this happen twice in roll overs and it twern't purty!
First couple was coming back from playing a gig at a ski bar and she hit "black ice" .... her Fender Telecaster knocked her out cold .. and she was out of it. Toyota 4-Runner.
Second was a buddy on his way to his cabin during deer season (By Elk Mt. Ski Area), in PA ... he hit a patch of "black ice" and his Ruger came flying out of the back. He was found wandering in the woods the next day in a state of severe concussion ... "looking for my friends" ... he called his wife on his cell.
Skis, guitar, boots, or rifle ..... get one of those $5.99 bungee spiders from Home Depot if you carry gear in the back of an SUV or wagon!
Cargo nets are cheap too.
Snow and ice is when we are on the road.