I understand the frustration first hand.
Had a 1985 Thomas given to me in 2004. I called my insurance co, went to the tag office and drove it home. I got into a mild fender bender in it in rush hour downtown Orlando traffic (on a firday too) and USAA promptly sicked their legal dept on me and totally denied me any coverage. "take us to court if you don't like it" was pretty much their attitude. I called around trying to find another carrier and NO ONE would give me a policy. Months were spent looking and calling everywhere. I started to get code letters from the city and with no ins, no tag (expired), and no way to help the situation I sadly had to give it away for the first person with cash in hand who could get it out of my yard. i got 500. Had to pay nearly 5 grand in a lawsuit for the fender bender with the "rare" "classic" 1984 land cruiser, and had to pay it back in installments for a year and eat ramen noodles almost exclusively.
To me the insurance is only good for getting me the tag legally.
Frustration? Yeah, buses are VERY good and inducing massive amounts of that.