It's impolite not to help roll when smoking with friends.
Sara is hanging out with some friends who are rolling up a bunch of smokes.
Sara wants to have a smoke right away.
Sara lights up a smoke and shares it while helping to roll up a few.
Sara starts smoking while her friends are finishing rolling the others.
Sara's friends are satisfied and feel like she is contributing to the rolling.
Sara's friends think she is rude for letting them do all the work.