It's very annoying. I'm doing Uber to pay for classes and I often have to nod my head and say thank you when people say that to me. I hate the assumption it makes and yet I'm forced to tolerate it if I want good ratings. Of course I think you should be free to reply hail satan or whatever you feel like but I know that's not the world at live in, there are consequences. I hope we live to see the world change and humans outgrow such primitive and repugnant ideas but it's hard to imagine most of the indoctrinated ever waking up and letting go. Sad and frustrating.

If your intentions are to pick on him (her), i think that you are doing a great job, but if your intentions are to enjoy your day and have a wonderful day unmolested by someone else, then all you have to do is to control your emotions and not get offended by someone with low compression in the matter, that is what should ofend you, someone who know less can get in to your head, try to be better for you, not for others, don't get offended by a person who knows less than you, because your offenses show how strong your maint is. Just be happy by looking and hearing low IQs in your surroundings trying to make sense of the reality. If you are smarter, its your responsibility to understand whats going on, if you don't understand, then investigate or have someone else to take control.

You should reply with have a blessed day too!
Blessed by whom is where the can of proverbial worms come into play!

Getting upset every time someone says something with religious connotations to it is only going to make your life more difficult. I had a manager that, when she found out I was atheist, used to deliberately talk about religion in meetings and then single me out as an atheist. Ex. “ We all believe in a higher power, that there’s someone watching over and protecting us. Well, all except Alicia. She’s atheist.” For reference, this was a home health care company, so no reason to bring religion into anything. I tried calmly and professionally discussing how offensive it was to me and asking her to stop, but she just got worse. What the experience taught me is that I can either roll my eyes and move on or be miserable. I chose the former. In a situation where someone is blessing me or saying Merry Christmas or some other good-faith phrase, I choose to take it as “hey, that person said something that they feel is nice and I’m going to appreciate the thought.” I don’t have to agree with their beliefs to appreciate a nice thought.

I just say back. "And good luck to you"

Depending on which retail service you work for try going to HR or even outside the actual store (my company has a phone number outside our store if you aren't comfortable speaking within). In the company I work for religion is to be kept out of the workplace. Food for thought especially if you need to keep your job - if not, hail satan sounds good.

If he/she is saying it directly to you then, try speaking him/her in private. Or, add "or for us not religious, have a great day" my e, they'll take the hint.

This made me smile.

There is a tradition in our family, that developed from one of our ancient grandmothers.
As a child, she got pulled up for the use of profanity in vexing situations.
Her mother told her, that whenever she needed to swear, to just say "Bless You", or "Bless them"

So now, when we hear someone in on the joke say "Bless You", or comment on a group of people and say "Bless Them", we know what they REALLY think.

My recommendation is to answer with a phrase that conveys your discomfort, by putting them in an uncomfortable condition without being insulting.

I might be tempted with something really flowery like
"And a blessing upon your ancient ancestors and their distinguished progeny", followed up by a deep bow and a flourish of the hand.

In order to retain our sanity in the face of of this type of mindless drivel we are sometimes driven to verbal retaliation. I use a simular tactic against those who cannot formulate a sentence without persistently saying ''You know''. Every time they say it I respond with ''I know''. In an amazingly short time you can see the brain engage and an effort to think about what they are saying is evident. So well done you.

I usually respond with "have a good day yourself" if their aware enough, they'll figure it out.

No, not a good idea. Take the person aside and suggest something else.

It irritates me as well... mostly because I don't like being told to do anything...no thanks, I prefer to have a shitty day...ugh

Irritating

I understand your frustration. It may be considered to be nice, but on some level, it's still an assertion that their beliefs are relevant in the work place. I saw a truck today advertising pest control, with Jesus fish symbols on it. I guess that was a signal to Christians that they should assume the business was more honest and scrupulous than none Christian bug killers?

A physician's Assistant (PA) use to say, "Have a Blessed Day" as he was going out the door after an exam. He never dwelled at the door long enough for me to tell him his comment was inappropriate and leave religion out of my medical exams. He didn't last very long at the doctor's office. And I never said anything to my MD. Otherwise, he was a great PA.
I'm glad I'm retired and don't have to deal with religious bosses.

I think some people use 'blessed day' the way other people use 'Oh God', it doesn't really mean anything other than have a good day.
Personally I find being honest about my atheist views but not pushing them has been good.
I hear 'Everything Happens for a Reason' A LOT! And crazy part is it's from my pot smoking, heavy drinker, nudist Christian friends... I usually reply gently, that I don't like that phrase that I prefer to think, "With the right attitude most situations can be an opportunity to learn and grow into something better."
Most of the time the response is WOW, I like that a lot better.
If they push I'll say, I don't like the idea of someone or some entity intentionally bringing pain.
This past weekend someone I talked to that way, gently, not from a place of offence, actually came to me and shared that she is having doubts about her faith.
We need people who give the 'hail satan' response, but I think a gentle response goes a long way as well.