I had insurance once upon a time. Then I realized it was a waste of money. It's been a few years without it, now. On my family plan, we've gone though 2 clamshells, 2 LG Chocolates, a DInc, OG Droid, Fascinate, and Rezound. We never needed insurance on any of them.
So quick math on how much money I saved in a year (on insurance):
4 Phones x $6.99 = $27.96/month
12 months of $27.96 = $335.52/year
Now multiply that by about 3 or 4 years or however long you go without it, and the savings add up.
Just buy yourself a sturdy case for $40 or so. You're still saving in the long run, and your phone will be protected.
But please, don't do weird crap like leave your phone on your lap when you're driving, or be around a swimming pool with your phone in your pocket, or hold your phone over a sink or toilet. I've heard ridiculous stories throughout the years.