Why is sarcasm a liquid, but anger is a solid?

They say "dripping with sarcasm" but not "dripping with anger." They say "filled with white hot anger" but not "filled with medium cool sarcasm."

You do hear the phrase, "tepid sarcasm." That's almost the same as "medium cool" and doesn't denote liquid or solid. Although, I guess "tepid" is more commonly used with reference to liquids, while "Medium Cool" is more commonly used as a movie title.