Something that drives me nuts is when people tell you to "have a good day." To me it puts pressure on you to have a good day. What if I do not have a good day? Then I'm going to sit there at the end of my not so good day and resent you.
How do you make someone to have a good day anyway? Do you have control over their day? Will saying "have a good day" miraculously bring about a good day? "Have a good day" is not the only phrase which is aggravating.
Saying "have a good day" is in line with saying "good morning". When someone says "good morning", are they assuming it's a good morning? What if it is a bad morning, or some other type of morning? It's not that I do not wish for anyone a good morning, I just don't expect you to be having a good morning.
Whatever happened to just saying "hi" or "bye", the simple greeting and farewell? Perhaps an "hola" or an "adios" will also work well. These impart no expectation on how your day is progressing or how the rest of your day will be. There is no chance for them to leave you resentful or disappointed because you are not having a good morning or the rest of your day turns out poorly.
Instead of saying "have a good day", replace it with "wishing you a good day." Therefore you are not commanding me to have a type of day. It also let's the receiver know you are wishing the best for them, even though it may not turn out that way.
There are many phrases in the English language which are taken for granted. They are often out of context or overused. This practice goes far beyond "have a good day" and "good morning".
Even though I'm complaining about these phrases, I'm guilty of using them on a daily bases. Almost everyone uses standard greetings or farewells. Not using them feels awkward.