Every day at my old job, when I'd see my boss, my mood would immediately plummet. He was the kind of person that didn't understand my workload, so regardless of my performance, there was always something I could improve on. Of course, in the right circumstances that's a great attitude to have, but what I'm saying is that he always has criticism for what I'm doing. So basically I hated him because he had unrealistic expectations of my capabilities (not as an employee but as a human being). But, every time we walked past each other in the store, he'd smile and say "Hey, how are you, man?" and I would reply in the affirmative, sometimes asking how he was, too.
But I think it's stupid that we pretend to care. He doesn't care about how I'm doing just as much as I don't care about him, and even if I'm having a rough day I'm still obligated to say "Good." That's my biggest thing.
When you're in public, and somebody asks how you're doing, you are socially obligated to respond in the affirmative, regardless of the truth. Of course, it wouldn't do to tell a stranger how you really feel if you're having a rough day, especially when they were simply greeting you, but I think it's stupid that "How are you" is even a greeting. In fact, when somebody says "Good morning" to me, I don't even like being obligated to repeat it. What if my morning has been terrible? And that's why, as silly as it sounds, I just say "Morning." I try to make it sound natural as a shortening of the former, but in reality I don't want to feel obligated to lie if my day hasn't been spectacular, and when I was working at retail, any time a stranger said "good morning" it meant that it wasn't for me.
I suppose we all get used to these masks that we have to put on at work or simply in public, but to me it just seems ludicrous. That's why when I go out, I try to break through that facade and touch their day in a way that will make them truly smile. Saying "Have a good day" means literally nothing when you're just saying it as a goodbye. But if you can make them talk about themselves a little bit, you can connect with that person, and that same "Have a good day" magically becomes genuine. People don't want to make that effort of starting a real conversation, but if it does happen you'll remember it the next day. I think one of the biggest reasons I don't have conversations like that is because I find the prospect exhausting, but if I had infinite energy to talk to people all day, like that, I feel like it would be strangely productive.