That is included in the above figures Tiffany. They are not considering the wholesale price but the grocery bill as a proportion of income.
Food is historically cheaper today than it has ever been for a US resident. It's a poor decision in terms of the best economic use of your time, to grow your own food rather than simply buy the healthier food at the supermarket. If you enjoy it as a hobby fine. We grow a few things here so the children can enjoy watching them grow and then eat what they grew, but for the bulk of people with normal jobs it is stupid to promote growing the bulk of your food and connecting it to a better economic strategy for life.
If you buy a balance of fish, meat, eggs, veg, fruit, bread, rice, pasta eat them in moderation from any supermarket and exercise you will be perfectly healthy and live a long life.
There is no evidence that modern food, if you eat a balanced diet and get moderate exercise, is bad for your health or that modern foods are "loaded with toxins" that your body cannot process and excrete. That is just hype that stupid people believe.
Any qualified nutritionist will simply tell you to avoid too many processed foods with lots of added salt and sugar and to drink plenty of water and get exercise.
Simple proof look at what Olympic athletes eat. I know several. They eat healthy food and are very strict about what they eat and when they eat it, but they all buy the food from supermarkets.
If supermarket food was unhealthy, at all, the marginal difference would show up on the track and in the swimming pool and the winners of the medals would all be found to be eating home-grown organic produce.