Earlier quoted context omitted.
Both happened because state was weak and decomposing. The revolutionary activities in Russia were long. Neither happened primary because of famine, both were in the making for years. In both countries, pleadership seen issues years and years before but was incapable to fix them.
It's hard to separate these things but I've studied, especially the Russian revolution fairly in-depth, and the sense I get is that people were feeling extremely desperate because of the food situation, and when they saw how incompetent and aloof the government was, how unable to solve their problems, the resulting feeling of helplessness and hopelessness was the last straw. I believe if food had not been an issue it…
Also, the way people talk about is as if hunger implied revolution. Most hungry places most of the time are just that - hungry and disordered. Organized revolution requires pre-existent groups, arms, competent leadership and especially weak state. When state is not weak, it will suppress the revolutionary activity with zero issues.