My dog eats random things off of the ground?

I have a small chi mix. He's about ten pounds and maybe once every two/three weeks he starts going around the house eating things off of the carpet..little bits of lint or whatever he can find. And he doesn't stop there he will chew huge holes through my sheets and blankets as well. I have 2 other dogs as well and neither have picked up this habit. He is the most spoiled of the 3 so i know its not a lack of attention... any idea why he does this?