Yes and no.
I agree that we'd need more information if we wanted to conclude that the phrase was being used to be deliberately offensive, but it's still problematic even if no offense is intended. It ignores the fact that non-Christians and/or non-theists exist. It marginalizes real people. The fact that the speaker might not realize that these non-theists exist, which I suppose explains the speaker's insensitivity, but it still leaves the non-theist with this near-constant message telling him that there's no space for him in that community... or that what space he does have has been granted on the basis of an assumption that he's something that he's not.
How does it ignore that non-Christians exist for one? As I said, Christians aren't the only religious people to use such a phrase. It could be used with a spiritual feeling indicative of any number of religious backgrounds. Pagans often use the word blessed/bless/blessings for example.
The only way I can assume that "have a blessed day" wasn't meant to offend is to assume that the person saying it had absolutely no idea that they might ever encounter an atheist, which is offensive itself for different reasons.
That, my dear, is ridiculous. It simply isn't said to offend at all. Why on Earth would someone wish blessings to offend? "Come to Jesus" okay, "You are going to hell unless you repent" alright, the same basic thing as saying "I wish you have good things come into your life today"...I just don't see it.
Apparently, "that's white of you" didn't have racist origins.
I cant believe that.
As I mentioned a few posts back, it only went into widespread use in the late 2000s. Virtually anyone who was raised to say it is still a child.
"Widespread use" means what exactly? that no one ever used it before it apparently "blew up"? No. Sayings and phrases go in and out of fashion, much like names do, it doesn't mean they were never used before or after they were "popular".
That's not quite the same thing, is it?
It's not reasonable to expect people to put thought into reflexive exclamations - if they were thought out, they wouldn't be reflexive exclamations. We're talking here about deliberate communication that, hopefully, the speaker has put at least a bit of thought into.
Actually, it kind of is. If the phrase is something ingrained enough as most people say "have a nice day" or "thank you come again" or "thanks, you too" or "see you later", then it is as reflexive as any of those others. And it simply does not mean that it is a preaching thing or intent to be offensive. If someone rings me up at the gas station during a snowstorm or something and says "you be careful out there" is them saying that going to make me
more careful? Are they saying it because they think I'm
not careful? Do they think I'm going to hit someone because I'm
inept at driving in the snow? If one really wants to be offended, really wants to look to find how someone could even possibly, in even the very slightest way, be judging them or insulting them...they can find a way to do so by reading far too much into a passing phrase of what was probably most intentionally reflexive good natured habit.