Perfectly normal to have a vegetarian pet thats supposed to be an omnivore (I had a vegetarian rat), but in my experience a dog that eats grass is doing so because it has an upset stomach.
plant him a pot of wheatgrass, its better than whatever crap is on your lawn.
Think your dog is stupid. :/
'Twas a cutlass swipe or an ounce of lead
Or a yawing hole in a battered head
And the scuppers clogged with rotting red
And there they lay I damn me eyes
All lookouts clapped on Paradise
All souls bound just contrarywise, yo ho ho and a bottle of rum!