Straw. Light, remarkably tough and effective in keeping the sun at bay while remaining well ventilated. Not so effective in the rain without a plastic cover, simple enough to rig with a plastic bag and rubber bands.

Yes, they wear and get torn up. Or as I like to say: They develop character. And when they become too decrepit to remain functional they get replace, or demoted to party night hats where it is all funky form over practical function.