Eating half the meal, then sending it back
“Um yea, it took me a while to figure out this steak wasn’t to my liking. If you want, you can just give me half a new one.”
Asking for a “rush order”
Rest assured, they are cooking your food as fast as possible. That’s how kitchens work. How exactly do you want them to handle such a request? Cook it at twice the heat?
Asking if things that are gluten-free are definitely gluten-free
If you are actually allergic to gluten, you should probably know that the fruit salad does not contain gluten, but the bread plate with a side cup of wet flour for dipping probably does. If you aren’t actually allergic to gluten, YOU ARE PART OF THE PROBLEM.
Substituting an egregious amount of items
If you want a bacon pizza without cheese or crust, you might as well not be ordering anything in the first place. It’s a pile of sauce and bacon, dude.