One "London Fog Tea" please!

On Thursday Night
4 of us went to eat 보쌈 (Steamed Pork) near CGV theater for dinner. Strangely, I have been having upset stomach since that morning. As the deadline is approaching, I must be having some sort of stress.
Although I told my lab supervisor I wasn't feeling great, I joined them for dinner.
보쌈 was delicious! One of my favorite food! So I couldn't say no
to that. Almost to the point that my sickness looked fake. (Haha)
Don't get me wrong. I am not still feeling great.

Anyway,
After dinner we went for coffee across the cafe. Unfortunately, there weren't any Starbucks or Coffee Bean nearby. After all, this is Daejeon.
There, we each ordered our drinks. When my turn came up, without any hesitation I asked the cashier, "Do you have London Fog Tea?"
The cashier looked at me confused and asked, "What is London Fog Tea?" At that point, all others around me looked confused as well.
So I explained to them, "You make it with Earl grey tea, syrup and milk." and her next response was,
"아! 홍차 라때!"
and suddenly my roommate's response was "I thought you were ordering something fancy but it's just 홍차라때!"
So, I made a fool out of myself. I only ordered that thinking that it might comfort my upset stomach but apparently it is a specialty tea!

Well... It is a small culture shock I think.
surely, people in Seoul knows what London Fog Tea is!