Funny, I’ve asked this exact question multiple times, and the answer I always get is that you just get fucked. You pay full price for the first vehicle, and then 90% of full price for every extra one.
Maybe it’s Georgia? I carry the minimum for the state (Liability + Collision), but then bump the Liability because I now live in a high cost of living area. So if I’m in a wreck, I get nothing, but the other guy gets a nice check for his car and his medical bills are covered.
My car insurance would be WAY cheaper for me to just drive one of my shitboxes 100% of the time than it is to split my mileage across four vehicles. But I make it up by being pretty handy. When one of them breaks, I have multiple other cars to drive while I wait for parts in the mail. So I’d still say I come out slightly ahead as far as costs go, but most of my ‘savings’ go straight to the insurance company.
There’s this scene at the start of War of the Worlds where the hero races his classic muscle car up this tiny neighborhood street at full tilt, exhaust notes at full blast, and I think he even screeches the tires by slamming the brakes pulling into the driveway. Then he walks up to his neighbor and they’re all chill with him. In any other world, the neighbors would have him in handcuffs.