pairings...
Because they give Wincesters shout outs. They give Dean and Cas shippers shout outs..
They break that fourth wall so often that honestly fans can make canon based meta writings that sort might give them a leg to stand on...
If things are said on the show it becomes canon...
There for Cas is seen has having a crush on Dean... because Balthy said it... and Dean didn't flinch...
Dean himself has come on to Cas... sure he was being kind of douchey at the time, he didn't want to be locked up, Castiel was mad at him... But the whole last time someone looked at me like that I Got Laid...
Everyone and there mother thinks Dean and Sam are a gay couple from the outside... therefore why is it wrong for the wincesters too?
I really wish the show wouldn't do these things. It doesn't help the people who try to assist it's canon.
Also though... the thing is... I do see CANON moments I can apply to my LOVE of Cas/Dean. I know not everyone will interpret them that way. But that doesn't make my POV less valid. I wish people would also just learn to accept, grow up and tolerate different POV.