FWIW they almost certainly didn't write on a cigarette package in this instance ;o)
It's just the name of that type of maths because people used to use whatever small, available, piece of paper was around - so cigarette packs some time ago (you definitely could write on them with a ballpoint pen (ie un bic).
Getting tangential, napkins to me in the UK have always been cloth, and we have serviettes (a French word, meaning sheet IIRC) made of paper to wipe our mouths with.
Our language gets more and more influenced by USA "English" usage, so perhaps youth would just call it a napkin. People do say 'paper napkin' but without the qualifier it's a fancy piece of cloth [to me].
