Tires that wear on the outside are an indication of underinflation. Tire size/load determine what pressure is needed. My suggestion is to step up a grade or two when you replace those tires, to something that will allow you to increase the pressure (assuming that you stay with the present size tires).

Insurance is a gamble that most all of us take knowing that the odds are we will lose in the long run. Anyone who thinks otherwise must also think that insurance companies don't make money. I have to include myself, however, when I foolishly say, "It's easier than saving."

Realistly, liability issues are probably the most important.