That depends on your position on the food chain. Many don't own valuable enough cars, furniture etc to worry about insurance. Insurance is good for peace of mind but for week to week living it's not a priority.
Third party insurance? See my post above. Hit the wrong car and you are screwed. Their insurance will pay for their damage, but the insurance co will want to get that money off you and they have years to do it.
If you have a mortgage , insurance is compulsory.