I don't think communism is immoral---I see totalitarianism as the thing which is immoral, and you can have totalitarianism with or without a market economy;
The correct question to ask is whether you can have communism without totalitarianism.
Indeed. As far as I know there hasn't been a peaceful communist society ever. Except maybe after all the dissenters got deported to gulags of course but that would be a form of "peace by genocide".
A couple of years back I stumbled across this diagram on reddit. Since then I've kept a list of all illogical arguments, quackery, irrational ideas and similar nonsense, to pass the time. The count as of today stands at 1229 irrational ideas (a few could be debated perhaps). Hopefully you'll have a laugh or two! Any additions let me know!
Link to the list:
https://docs.google.com/spreadsheets/d/1T3HQ6TnCg6Q44WzpJPFxLvfqbfvKmT5RqvpGI3ji1y8/edit?usp=sharing
And the original diagram: