My last purchase (CFTBL, so was no small amount), when I handed over “all hundreds” I watched the guy count every dollar. At the end he says “it’s short. I replied, no, it is not, please count again and make sure 2 bills aren’t stuck together”. He counted again and saw his mistake, but he even said before recounting “ go ahead and start packing up while I recount”, I of course said no to that as well.