My car insurance is 10% cheaper due to keeping my car in a residential parking area as opposed to in my garage! My best guess for the reason - aside from that t

My car insurance is 10% cheaper due to keeping my car in a residential parking area as opposed to in my garage! My best guess for the reason - aside from that the statistics say the risk doesn't require a higher premium - being a person, I want a proper reason ;) - is that on average a garage affords a thief more privacy and gives them (compared to on-street parking) a good idea which house to look in. (The funny thing is, my parking spot is numbered. But they never asked me about that.)