Well, that's only partially correct. Drunk driving and speeding tickets will have no effect on your insurance because both of those issues apply to the policyholder and any additional named parties, not to the vehicle. Since your buddy isn't on your insurance, he gets the premium penalty for the DUI, not you.
In the event of an accident, the driver's policy covers bodily injury while the owner's policy covers physical damage. Typically, your insurance company would also seek partial compensation from your friend's carrier as well, and you both will be affected.
Also, where the hell do you live that parking tickets affect your insurance? Even if you don't pay them, the only consequence is that you can't renew your registration until you pay them off. Or if you live in a city that uses parking enforcement to generate cash, your car gets towed and you have to go pay it off immediately.