We can surely criticise one without having to immediately complain about the other, can't we?
Edit: To be clear, my problem with this is that to pretend that there is only a choice between 'capitalism' and 'communism' is a false dichotomy.
For most people a non-capitalist system is necessarily socialist/communist. So the response is apt for most situations.
> there is only a choice between 'capitalism' and 'communism' is a false dichotomy.
I fully agree, there are nuances that are not considered in what is traditionally defined as communism/socialism/capitalism.
But it's important to note that most people understand things only in black and white, and never the shades of gray.