Discount Tire add on insurance

There have been times in my life when money was tight, and buying this (it's basically insurance for tires) seemed like a good idea because I didn't want to chance an unexpected bill for a ruined tire. Nowadays, money isn't so tight and I can handle a surprise bill, so I don't buy the coverage. I don't ruin tires often, so I figure I'm coming out ahead by not buying it. They would not sell those add-ons if they didn't think they could come out ahead on them.

I get irritated when any tire store tries to tack on this coverage without telling me, though. Hibdon Tires Plus has tried this a couple of times, and I make them take it off or refund it.