Here are two examples:
1. Amazon shopping. You can buy anything for your life in one place, and the credit card receipt just says, Amazon. Thats too broad a bucket to really track where your money is going. I like to understand, for example, what I am spending on consumables for house upkeep, like light bulbs and air filters, separately from things like bike accessories.
2. Splitting out alcohol and other highly discretionary purchases from grocery shopping. Lets say I want to budget for alcohol spend as a way of gently trimming back my consumption. Or chocolate, candy, etc. Would be nice to be able to do this quickly. The ideal would be to simply scan the supermarket receipt and let OCR figure it out for the majority case (aka the 2 or 3 stores I shop at every week).