That was my first guess as well. People who are wealthy enough to both a) not be affected by it will generally be wealthy enough to not do their own shopping.
I was thinking more like people who live at home with their parents, and their parents buy the food. The top 20% of earners start at $80,000/year and those folks are certainly seeing the impact.
Bear in mind that's individual income. If you're looking at family income it's around 130k (per the latest census data).
My household makes more than that and the grocery prices are still hitting us hard. Went from spending ~$150/month to spending almost that much per week. We're not eating steaks or anything and we cook from scratch. It's wild.