Because pies are not so lethal, except at higher speeds, in which their metal containers might bash your face, as painfully as a swift punch.

If it is, then yes. She did. And survived.
 
She’s THAT awesome.

I wonder how lethal strawberry pies are…

Pies aren’t artillery you goobers! They’re anti-personnel weapons!  
So my headcanon is that pastries in general are lethal when properly prepared. I will not explain what this preparation process is. Basically, if the pastry is launched, it’s gonna hurt. Which means; Yes, Pinkie Pie was (potentially) trying to kill mega-spike. And yes, Blueblood is a bastard. Maybe slingshots with cupcakes inn them are the equivalent of guns?

@Jackarunds:
 

If A, then B.  
The above is a statement.  
It is a statement asserting that there is a causal relationship between A and B.  
It asserts nothing about the actual truth value of A or the actual truth value of B.
 
The truth value of the statement itself (whether or not there is a causal relationship between A and B), however, is actually true when the conditional part of the relationship in question (A) is false. The statement if A then B itself is only false in the case that A turns out to be true and B turns out simultaneously to be false.
 
So, because pies are unquestionably not artillery, this picture’s question about the logical relationship is to be answered “Yes.” The causal relationship between (pies being artillery) and (pinkie having just shot herself in the face) is a true and correct concept until we see the specific case where pies are artillery and pinkie didn’t shoot herself in the face.
 
TL;DR. Pies aren’t artillery. What kind of nutjob are you :V

@Zombie_Trotsky  
Are you kidding, custard has been known to kill a pony in 5 seconds.

I believe eating pies and war pies have slightly different recipies. Either that or the pie catapults can impart enough velocity that a pie can cause enough injury to (temporarily) disable a buffalo.

Would regular custard be “lethal?”

@Prof.NightJack
 
Nah, it just means that the pie has faux filling in it.
 
It’s a plaster of paris mixture, like all the big stunt agencies use.

Pies aren’t artillery.  
Therefore, yes, if pies are artillery then pinkie just shot herself in the face.

@Pinkie:  
I’m not so sure about the “OK” part, Sugarcube. :P

@Pinkie☺Pie  
Then shouldn’t the pie not have a filling?

I….never thought about that. Hmmmmm.

Nah, it was a blank round. I’m OK!