Insurance Co. says car must be in a locked garage

I’m not really concerned about the cost of the cars, but I need liability to drive. I can understand the insurance’s company point of view, but I’m more concerned with a low-cost alternative for me. Any ideas? Do you guys put all your old cars in a locked garage?

I have liability only through AAA (California State Automobile Association). They do not issue full coverage on a classic car. I drive my car anywhere and anytime I want...