Back in the 1970's my in-laws raised cattle and were mostly on grass (the cows, I mean. Well okay, me too, but that was different). There was a difference in flavor & texture. I think it's because feedlot animals don't move much and eat high-protein food resulting in the animal equivalent of that mattress-man. I don't think most people would like meat that is more dense and less fat. The flavor difference isn't a big deal, IMO.