system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do people usually hold tobacco cigarettes between their index and middle fingers, but hold marijuana cigarettes using their thumb and index fingers?
gpt
It's because if you hold a joint with your index and thumb finger you can smoke it all the way down to nothing without burning your fingers opposed to the cigarette way. Since a cigarette has a filter you have space for your fingers.

EDIT: Punctuation.