How many people are really buying "pallets"? It's probably more like people picking up another one of those big 18-roll packages even though they're not at the point yet where they would stock up under normal circumstances. And that adds up to a lot (of a bulky product) in the aggregate.
While not pallets, I have read anecdotal reports here in NJ that stores are selling out of toilet paper within hours after opening following a restock, so it seems to be more than just buying an extra package every time someone goes to the store.
The only way I have been able to get any since this started is the store I mentioned elsewhere that is selling individual institutional rolls.
About 3 weeks ago I went to Walmart at 6AM to beat the crowds. I got meat (20lb tube of ground beef!), rice, flour, and a bunch of essentials. Checked the toilet paper aisle and they were out.
Went back to my car and while I sitting there, I saw people leaving the store with TP. Asked a lady where she got it and went back inside. It was gone!
Between the time I checked the racks and left the store (maybe ten minutes at most), they put out toilet paper and sold out! That's insane.
TBF, the many people who don't keep a lot of extra stock in the house probably got caught out early on even as the usage was going up a lot. So there probably are genuinely people who need it at this point and they're buying more than they usually do. (And, yes, a lot of people who are in the store for other reasons may well grab a package of TP even if they don't really need it and wouldn't normally have bought it.)
Reddit has had no shortage of photos of people rolling into stores and trying to push out multiple shopping carts full of toilet paper and paper towels. Particularly back before stores imposed limits.