The main "glitch" I see is that very few people outside of farming and forestry, in the very broadest of senses, have even the remotest comprehension of what it would involve.
At the very simplest of levels, essentially all of the UK's land is managed and it produces all of the great lanscapes that people like - in the wilder parts, very often due to grazing, especially by sheep. Take away farming, or farming at a level that makes economic sense, and the land will need managing, and that will not be cheap because it will be done by civil servants, and lambing at 2-3-4 in the morning, or ploughing for a 10-12-14 hour day Saturday and Sunday because it is finally dry enough, and suchlike, will come at premium rates, just for instance.