It sucks that they can't figure out how to fulfill online orders adequately. We have not done grocery pickup, but from the posts on NextDoor, it seems common to pick up and order with multiple items missing, but if you walk inside, they have them on the shelves. Some of it is the stock at the time they pull the order. I know our grocery stores are all stocking all day long (which is really, really, annoying when you are trying to stay 6 ft away and they have a giant pallet blocking the whole section), so an order pulled at 9 am for a noon pickup will be missing anything stocked from 9-12.
Costco has been fairly well stocked here. They have reduced selection of frozen hamburger, but I was able to get the 6 lb package of fresh, so I just froze it in smaller chunks. I didn't notice the TP since we never buy name-brand.
One other note - the two sodas you mentioned are not super common. I know many food manufacturers are cutting back the number of products so that they can increase production, so all the fancy Coke flavors and 17 varieties of Chex mix are no longer available. That could be the issue with the soda, not that it helps.
Mama to three boys ('03, '05, '07)