@mnem, You took the words out of my mouth (well almost), I was going to pen a reply along broadly similar lines and over here in the UK, even growing your own vegetables and fruit is not really a viable option for most people, especially the poorest of the population who either like me live in social housing or if you can afford your own home, generally it is going to be at the bottom of the market because land prices are so high that only the wealthiest can afford to buy a house with sufficient land to grow your own crops on. City dwellers fare even worse as many are forced to live in a flat with no garden space at all.
When it comes to shopping many people are forced to look for the special deals such as BOGOF (Buy One Get One Free) and other similar deals which 99% of the time are always on highly processed foods stuffed full of salt, sugar and nasty chemicals to help preserve it and other cheap fillers to bulk the food up, such as onions etc.
This also hits the retired folk hard with low pensions for instance, I know from personal experience that approx 82% of my monthly pension is gobbled up paying rent on the house, council tax, water and sewage rates alone meaning that I have to dip into my savings to meet the other monthly expenses and shopping. I can't get any benefits because my savings are over the limit to permit that so until my savings are depleted, I'm stuffed, and even when I will be able to claim benefits, I'll have to cut back on everything that I currently enjoy as benefits will not support my current lifestyle which is very basic.
So at the moment I'm having to spend my savings and my kids inheritance to keep going and things are very likely to get even tougher after Brexit because most of the working class voted to leave after falling for the untruths of the pied pipers leading the Brexit campaign, things like when we are on WTO terms we can enjoy cheaper food, shoes, clothing etc as a result of being free of the EU tariffs etc