I feel like in the American workplace we’re expected to be casual and friendly with everyone while also being acutely aware of rank. So if your boss sends a silly meme, you might want to reply with another silly meme. But if you go over your boss’s head and send an unsolicited “hey <first name of the boss’s boss>” email, you might still be in for repercussions. Just because everyone is on a first name basis and drinks beer together at happy hour doesn’t mean they’re really on equal footing.