Many Americans feel the same way about rye bread, and even Americans who hate Wonder Bread don't go in for Russian black bread.
I don't think corn grows in most of Russia. Except in the south, the growing season is too short. Italians and Romanians, though, did take to eating corn mush.
“I don’t think corn grows in most of Russia.”
They don’t. After the fall of the Iron Curtain (which is debatable - it still exists...), we exported many, many metric tons of corn to help them economically. It was meant to help feed the population, but they used it to keep their livestock alive! A Russian escort for our START team laughed at us for eating pig feed.