Can I just say that I died laughing and crying at this one moment?
Obviously, he is just ready to wipe out the entire mini-mart just because there is no homemade pie left. Lay waste to the small little store because it’s virgin defender did not carry just a simple treat.
But then there’s the obvious reason why he needs that pie. He hurt Dean. Like, really really hurt him. And it became very obvious when Dean refused to take him along and instead took Sam. So instead of staying in the batcave and moping, he did something about it. He over heard that the boys needed groceries, as was obvious by Dean’s meal of jerky, Reese’s peanut butter cups, and beer. So he walks in, first thing he grabs is some jerky for Sam. Busty Asian Beauties is added, because he knows that is Dean’s favorite skin mag. Next comes the toilet paper, because let’s be honest, you can never have too much toilet paper. Then comes their staple of beer, and a pack of eggs. Last but not least, he goes to buy the very last thing he needs to win back Dean’s trust. Pie. The one thing that he is so convinced would give him back the love and trust of Dean he so desperately wants back (because everyone forgets the damn pie). All he can think about is pie for Dean.
And this boy stands in his way of getting his friend back.
Castiel has every right to be mad and unleash his own apocalypse for pie. Because all he wants is Dean to love him again, as he used to.