The time period is 1923-25 Petrograd. Although not a biography Ayn Rand said "She lived the character". This is a time of State rationing and limited privatation called New Economic Policy(NEP). Tea seems to be readily available. The book isnt clear how it is obtained. Sugar is so scarce only saccharine used in the tea when served from samovar is only obtainable from NEP stores. Every politico, sociologist, psychologist, philosopher has an opinion of this book. My take Dont Fall In Love During A Revolution.
Jim
PS I found it interesting Google Books didnt give every reference to tea or saccharine in its search function.