Oh come on guys, he wasn't acting like a jerk (well yes he was but that's sort of the point). He was clearly distraught from the current events (Last Days of Superman) and his prior encounters with a Lex. You saw how fast he ran off to shave and change. Lois even recognized that he might be in too much of a rush.
He wanted his cape and family crest off Lex because, from his perspective, it's an abomination. Bottom line, he was just heated. The story doesn't reward him for his action (he actually gets his ass kicked) and Lois is constantly telling Jon that what his father is doing isn't right. But it's understandable to see where he's coming from in this very delicate time.