And when was it that you last broke a DVD?
I've never broken a DVD. I last broke a 5" optical disc in the 1980s when I threw a CD against a wall, demonstrating how impervious it was to damage. Wrong!
Put a disc away in the case after you are done watching it and this should never be an issue.
Disc 1 of my ST3(The one with the movie on it)had a hairline crack at the center. Every time I took it out of its case, the crack lengthened. I eventually ended up just rebuying it for 7 bucks at walmart.