Sure, and my Amazon example wasn't very illustrative of the kind of information that could be gleamed from tracking this at a more granular level. A more concrete example is that my wife and I were flirting with the idea of reducing our meat consumption (for non-financial reasons) and wanted to see what the financial implications would be. Another example is to try to accurately price out past trips we went on: some things normally get filtered under other categories, such as clothes or other products purchased specifically for the trip.

This level of granularity probably isn't worth it to most people, but I found it useful as an exercise to do once because it opened my eyes to insights about my expenses I never would have thought about otherwise. And if there were software that made this super easy to do (<1 minute per entry), I might still be doing it.

Some stores are modern-day general stores (Costco, Walmart) so you will end up purchasing from several categories on one trip (gift, groceries, home maintenance). YNAB, for example, allows for splitting a single transaction across several categories but you have to figure out what the cost of that individual item was.

It’s annoying to do in Canada where sales tax is not included. The fly in the ointment is that certain categories are tax-exempt (essential foods, kids’ clothing) but not others (prepackaged foods, adult clothing).

If your shopping trip is across three or more categories (gifts, clothing, food), you’ll have to figure out which items were tax-exempt before you can do any subdivision.