I used to take two - one with salt, one with pepper on holiday. They were just the right size. I'd have two or three filled with washing powder, one with a sewing kit, mixed herbs etc. On a picnic, if you'd taken enough photos, you and a partner could use one each for drinking wine slightly more delicately than swigging it from the bottle.
Packing for a trip recently, I did wish I'd kept just a few from the old days! It's funny... I bet if I showed my kids this photo, they wouldn't even know what it is!