@Animegx43
 
At least Twilight, Sunset and Fluttershy are all probably vegetarians, so of course they wouldn’t order a pizza that has meat in/on it…This would be mean.

@FancyCat2008
 
True from the look it. The square red and green bits are probably peppers and tomato maybe and there are definitely mushrooms on there.
 

 
Sunset Shimmer might be a vegetarian by choice even though she’s been in the human world awhile and probably doesn’t let it bother her if she encounters it, but it would make sense for the Humane Five to order vegetarian toppings simply so they wouldn’t freak Twilight out during her stay. Sunset Shimmer has probably explained to them at some point that ponies are Ovo-Lacto Vegetarians.

@FancyCat2008  
If it didn’t have pepperoni, then it ain’t pizza.

@Animegx43  
Except I can’t really see any meat ON that pizza… mushrooms and peppers yes, but no stereotypical pepperoni at least.

I think the idea is to point out that a former pony now eats something that has meat in it.

@TheAntiCat  
What are u talking about?

OP, you literally cannot just put words on a picture and call it done.  
What is the point of this image? Always ask yourself that before anything else.

But there’s no pizza…

What is up with the white dots?

What?