I never run less than 60 psi on my set of clinchers, and I have yet to pinch-flat in a race. For what it's worth, I'm 175 lbs, but I take it pretty easy on my wheels.
I figure that I'm spending $20 for 45 minutes + 1 lap of maniacal fun. I really don't want the fun to end after only 1 or 2 laps. A harsher ride is a sacrifice I'm willing to make.