Hey,
I've been working diligently to find a source of top quality grass fed beef. Some here have told me it's easy! I broadened my search to the whole country, and it seems to me there are only one or two that do not supplement their cows at least a little, in the winter for example.
E.g. From a raw dairy supplier in South East UK:
"The farm is an all grass farm, most of which is permanent pasture on the land on the Pevensey Levels. On the upper western side of the farm, grass leys that are rich in red and white clover are grown. The cows graze all these fields once the ground is dry enough 'to turn them out' in the spring, until the ground becomes too wet in the autumn. The cows are then housed indoors for the winter. They are fed grass silage in the winter that has been made from lush spring grass and clover. An organic pea bean and wheat mix is also fed to the cows to supplement their grass diet."
I've been phoning places, googling and asking around at the butchers near me, and I'm not getting very far. I get some pretty weird responses some of the time. One place I called turned out to be a distributor/abattoir not what I thought, they were really pretty hostile. One guy in a butchers was a bit slow, and didn't have a clue what I'd just asked him and started talking about the amount of fat on the meat. Another guy said something along the lines of "Well, yeah, I guess. I've seen the cows on the fields..." That didn't inspire me too much.