Those variations, the authors say, are actively defying the conventional retail categorisations that financial professionals and economists have long relied upon.
Categories including household appliances, pet care, mobile technology, fresh food and staples, dining, automotive, beauty, apparel, DIY home improvement, and leisure travel were all examined for signs of income-based divergence.
The findings show that the gap is not static, it is accelerating in some areas and holding flat in others, often in ways that contradict intuition.
In dining, for instance, lower-income households are actively pulling back while their higher-income counterparts intend to spend more; a bifurcation that reflects not just spending power, but confidence, economic outlook, and lifestyle expectation.
Pet care and packaged snacks, meanwhile, are already heavily skewed toward higher earners, a finding that may surprise those who assumed these categories as broadly accessible.