Wow, I just realized that I completely misunderstood the OP. I thought you meant that you were talking about words that you are saying you don’t think that people really say in real life. Now, I think you meant that those were words that you, yourself, say that people don’t say in real life.
My husband says, “I reckon,” all of the time and I can’t stand it. To me, it just sounds hillbilly, for some reason.
I was thinking about customer service type contexts whether you are a minimum wage cashier or a lawyer. American civility requires a liberal use of “Please, thank you, and you are welcome”. People don’t automatically do that in Western Europe and it is jarring to a American visitors. We are used to saying such things many times a day. It is very rude not to do so here.
Thank you for your time.
nope, all the time, all the time, sometimes, yeah, sometimes, all the time, rarely
For whatever reason, most of mine seem to involve the passage of time:
No, you read correctly first – words that I say, that apparently other people do not say. In the referenced thread, someone mentioned that people don’t actually say things like “meh” in real life. I actually do. So much so that my coworkers have joked about getting me the MEH hoodie from thinkgeekdotcom.
I use a lot of antiquated words and phrases. I use words like anon and elucidate as well. I find myself having to repeat myself (using dumber wording) to my customers quite often. I have a habit of saying “and with whom am I speaking?” instead of “who am I talking to?” which apparently confuses the majority of our customers.
Now look here…I’m a project manager, if I can get through a discussion with a customer, sales, etc withough using the word ‘deliverables’ I’ll be bloody lucky! 
I startled my Danish colleagues the other day by using the Farnsworth’ism, “Sweet Zombie Jesus!”. I got this “what did you just say?” look followed by laughs as they thought it was a great phrase.
I think “Oh, my goodness” had a brief spurt of popularity with “the kids” a few years ago. I remember hearing my son (now 21) and few of his contemporaries use it, and remember how incongruous it sounded coming from them.
I use quite a few words others don’t. I don’t like saying things other people do, it’s boring. But I do have to watch myself. I have answered a manager assigning me to a task with “In accordance with prophecy” and a bow.
The other day, I had to bite my tongue from telling a cow-orker that I was going to perform an Oedipal micturition. But I would have had to stand with a full bladder to explain I meant ‘Piss like a Motherfucker’.
or
“I’m afraid I must decline, but I appreciate the offer.”
What?
No, Thanks.
I have become, IRL, annoyingly florid. I don’t beg to differ, I just differ.
In the late 80s, I used “word” to agree with people, and in my neck of the woods no one used that outside of rap.
Ahead of my time, I was.
I’ve had to explain the meaning of gobsmacked more than once. I didn’t realize it was so uncommon.