The point can be made with the Eid which of course follow the month in moving through the solar year and at least are actually the holidays.
But I have ordered it at Le Marrakech in Saint Martin, a Moroccan restaurant owned and operated by Moroccans, where it is on the menu as Ramadan Soup (Harira). 
Have an Orgasmic Saturnalia is always worth a few chuckles as a reply.
I’d be tempted to say something like “Isn’t Christmas a holiday?” with a very confused look on my face…
The first time I was told to say Happy Holidays and not Merry Christmas was when I worked at the front desk of a high end retirement home, because some of the residents were Jewish (Hawaii doesn’t have a large Jewish community). If someone wished me Merry Christmas, I’d reply Merry Christmas quietly (so others don’t overhear) or just thank them.
The significance of respecting those of other faiths really struck me one day when the sleeve of one of the residents lifted up and I saw her tattoo. And there was one man in particular who no matter the weather would always wear long sleeves. I was told it was to hide his tattoo. SIGH Thankfully I wasn’t on duty that day, but I heard that this man who was the quietest, gentlest, always friendly person suddenly snapped when a fellow resident (whom he saw almost every day) raised her hand to say Hi and he claimed she was giving the Heil Hitler salute!
On the other hand, there were a few residents who would yell “Merry Christmas” to me across the room, knowing which fellow residents present were Jewish. Double Sigh
Now, I usually don’t say anything, letting the other person take the lead and repeat the greeting they said to me. I’m even careful about Happy New Year around native Chinese people since it’s not their New Year. Less so around Koreans as the Lunar New Year (at least those I’ve met) isn’t as big an event for them.
“Bah. Humbug.”
Follow up with:
“If I could work my will, Every idiot who goes about with ‘Merry Christmas’ on his lips, should be boiled with his own pudding, and buried with a stake of holly through his heart. He should!”
Well aren’t you a pleasant person? For 2 words almost always meant in a positive way?
It’s not like Jews are allergic to Christmas, or need to be shielded from its existence. There’s nothing wrong with one Christian wishing another Christian a Merry Christmas while a Jew is in the room.
It’s something else to unknowingly say Merry Christmas to Jews, that’s less cool. It’s far less cool, downright insulting, to do it knowingly.
I think the key is “where I work”, a lot of people take “Happy Holidays!” as businesses saying, “We’re very happy to take you money, during what in the US has traditionally, been a Christian holiday where they exchange gifts, but we won’t acknowledge your faith, by saying Merry Christmas.” Or as they see it the WAR ON CHRISTMAS.
But to your question, since you’re at work, you can’t do some of the things I would suggest, so a polite thank you. And leave it at that, the more polite you are the more ticked off they will get.
I live in the liberal north-east, where there are lots of non-Christians. I have never run into this particular bit of rudeness. But if I did, I would probably do a double-take, and say something like “huh?”, expressing my shock that they took my well-intended words as a barb. and I think that would be okay.
You don’t have to respond at all. You each greeted the other, time to move on to the next thing, whether that be walking past each other, one of you ringing up the other’s order, or getting down to talking about that account you are working on together.
Oh – and at the end of the day, I would post about this bizarre rude person on-line, and get out some of my annoyance at them. 
Do people get upset by someone saying “God Bless You” after you sneeze?
I’m not religious, so I just give the polite “Bless You” but I take the “God Bless You” as a polite social norm and not an assault on my agnosticism.
I don’t keep people in my prayers as I don’t pray. I have good wishes for them or keep them in my thoughts. But if people keep me in their prayers, I take no offense. It is nice of them in my mind.
Isn’t taking offense to “Merry Christmas” a little much? Taking offense to “Happy Holiday” is also very silly. That isn’t even anything new. I remember that phrase on some of the Christmas cards my parents got when I was a little kid.
I had a classmate that used to say “I Bless You” after a sneeze.
I always thought that was a little slice of awesome in 8th grade.
Once again, this thread isn’t about taking offense at being wished “Merry Christmas.” We are talking about people who get offended about being wished “Happy Holidays.”
There is a certain cashier at the local grocery store where my wife and I shop. It’s clear she’s a senior citizen and it’s clear she’s been a cashier for every day of her adult life. It’s also clear time has diminished her hearing and she has also become thoroughly unimpressed by the daily routine. It’s clear that, as soon as she hands a customer the receipt and change from the transaction, she has already moved on to the next customer. She might say, “Thank you. Have a nice day!” or throw in a seasonal greeting but, regardless of the customer’s response, her counter to the response is invariably a very nasal and drawn-out, “Uh-huh, shewer!” (She really drags ‘sure’ out to be a two-syllable word) and she is immediately focused on the next person in line, visually, aurally, mentally, and verbally.
That would seem to be the best approach to the seasonal zealots: Turn and look at the next customer (or appear to be searching for more, if there’s nobody in line) and call out, “Next?”
You’ve got a job to do, business to transact; you’ve moved on to the next interaction. Most people – probably 99% – would take the hint and move on as well. For those 1-percenters who insist on a confrontation, you could probably respond with “Security!?”
–G!
Happy Holy Days – Whatever your persuasion!
Man, I gotta stop reading these threads when drunk.
People who get offended about being wished “Happy Holidays” are morons.
Maybe ten years ago, when I was a bit upset at a snarky “Merry Christmas” reply to my Happy Holidays" greeting, I replied “What just Christmas? You want my New Year’s Day to be rotten?”
I’ve since taken to “Happy Solstice” greeting and any comment is met with, I’m sorry, but the Christmas date was stolen from Solstice celebrations.
“My uncle died in World War 2 defending the right to say ‘Happy Holidays’.”
Another retort might be “and a dreary, boring Christmas spent praying in a cold church all day to you and yours, just the way the Puritans and the Founding Fathers celebrated it.”
I think you’ve been whooshed, Nephew Fred. 
Happy Mondegren!
It’s May your wife be plagued with runners in her hose
I just say, “But I’m not Christian,” with a small smile. Let 'em flail at the rising tide of secularism all they want.