I thought it was pretty clear that it is colloquial language, and that the italics are for emphasis... For example, "They blew his head off.

In the future, maybe you'd be better served to trying asking the other person how they meant it, rather than jumping to correct them.

Unless your actual purpose is mainly to aggrandize yourself by dunking on someone else by correcting them... In which case you should just carry on, as you have been doing.