I'm not actually sure I'm too worried about this.
Subsidies to established industries like farming are, as far as I'm concerned, ways of giving money to landowners and capitalists. If I particularly want to buy locally- or British-grown food I use farmers' markets, delivery boxes, farm shops, or particular retail chains, but generally, unless I'm looking for specific types of seasonal produce, I'm not that worried about where Tesco or M&S source their fruit and veg, and when I am, I'm more worried about food miles than anything else.
The government seems to share that view, and is now subsidising farmers to preserve and re-wild land they can't profitably use for crops instead of, via the EU, subsidising them to grow food they can't find anyone local to pick because they pay their workers so little.
I find it difficult, therefore, to raise much sympathy for the farmer who can't find people to work for low wages, just as I find it difficult to sympathise with the plight of US fast-food outlets who can't recruit because the pay's so bad.