Why are people like this?

It’s been pretty abysmal since before new years, and this was the first decent paying order i’ve seen in weeks. It was a 96 item order bit she had everything set to “do not sub” except for milk and eggs (that of course they didn’t have), also had a couple of items with weird notes, Whatever, but she finally once I’m almost done shoppings she starts telling me to start with pantry items first, cold last. Like ma’am this is just how I shop for anyone, relax. Then after delivery she messages me asking about a tuna sub, No there was no sub on your shopping list. A few days later she tips and hits me with a 4 star for missing and wrong items. Like c’mon lady you’ve gotta be kidding me with that. Can January just be over already! Lol