The Promotion from Hell

I love my job. I have worked at the same coffee shop for 3 years, for two different owners and I am now the person that has been there the longest. You could say I'm a veteran.
But I actually love my job. I love what I have to do, I love the other girls I work with, I love my boss and I love (most of) the customers. I love making fancy lattes and being so good at my job that I can multitask with 4 different things at once.
I love my job.
But there is one time a year when I would rather swim in a pool of jellyfish than put up with another bloody customer. That time of year is summer, particularly when cold drinks are the thing.

I cannot stand making cold drinks. It's time consuming, in the way of everything and the way customers order their drinks makes me want to scream!
Now, it was worse before the new owner took over and the ice machine would break ALL THE TIME! The new owner fixed that, and I'm very grateful for that, particularly because ice is the base of most cold drinks (duh).
However, this time of year is still TORTURE.
There is always a promotion in the summer when a certain time of day or day of the week the blended drinks are less money. It makes sense. I'll admit that. It's hot, the drinks are cold. People love smoothies and milk shakes 'cause they're delicious.
But because they're so cheap during this promotion, people order SO MANY of them. Especially teenagers and children. And let me tell you, I already have an issue with the children/youth that comes into my store (spoiled), so add 6 different frozen drinks to that and you have a recipe for a massacre.
The main problem that I have with teenagers ordering drinks with their friends is the way they go about it.
Here is a hypothetical, yet factual conservation that I have with groups of teenage customers:
Me: "What can I get you?"
Girl #1: "Can I get a frozen hot chocolate with whipped cream?"
I go about making the drink and once ringing her in, hand her the finished drink.
Girl #2: "Can I get a frozen hot chocolate with whipped cream?"
The process continues once again until I get to the 4th kid only to find I have to make ANOTHER frozen hot chocolate with whipped cream.
What is the problem with telling me at once that these 6 people are all going to get frozen hot chocolates? That way I can make them all together and they will all be ready at the same time. Instead, I get to take the same order from 6 different snot-nosed teenagers that think they are the hottest thing since sliced bread.
I don't know if I'll be able to handle that group of kids this summer. My town may end up on national news, displaying the headline "6 youth maliciously slaughtered in small coffee shop".
The other issue that I have is when a family of 5 will come in and order 5 different drinks that do not have the same base whatsoever. One strawberry smoothie, one mango smoothie, one frozen hot chocolate with soy milk, one chai chiller with hazelnut and one chai chiller (Wait! Maybe it will be the same!) with lactose free milk and vanilla. Nope, not a chance that any of them will be in any way similar. Instead, I get to spend the next 15 minutes making 5 different drinks for this family. Enjoy the rest of your car ride home, assholes.
So the next time you go into a coffee shop during a summer afternoon and wonder why the barista girl is being a snooty little twit, think of me and my message here! I've had enough and if you give me lip, you may end up the same way as the girl that was brutally murdered in my town a year and a half ago. Too soon?